--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/kernel/eka/memmodel/epoc/flexible/mchunk.cpp	Mon Oct 19 15:55:17 2009 +0100
@@ -0,0 +1,688 @@
+// Copyright (c) 1994-2009 Nokia Corporation and/or its subsidiary(-ies).
+// All rights reserved.
+// This component and the accompanying materials are made available
+// under the terms of the License "Eclipse Public License v1.0"
+// which accompanies this distribution, and is available
+// at the URL "http://www.eclipse.org/legal/epl-v10.html".
+//
+// Initial Contributors:
+// Nokia Corporation - initial contribution.
+//
+// Contributors:
+//
+// Description:
+//
+
+#include <memmodel.h>
+#include "mmu/mm.h"
+#include "mmboot.h"
+
+
+DMemModelChunk::DMemModelChunk()
+	{
+	}
+
+
+DMemModelChunk::~DMemModelChunk()
+	{
+	__KTRACE_OPT(KTHREAD,Kern::Printf("DMemModelChunk destruct %O",this));
+
+	MM::MappingDestroy(iKernelMapping);
+	MM::MemoryDestroy(iMemoryObject);
+
+	delete iPageBitMap;
+	delete iPermanentPageBitMap;
+
+	TDfc* dfc = iDestroyedDfc;
+	if(dfc)
+		dfc->QueueOnIdle();
+
+	__KTRACE_OPT(KMEMTRACE, Kern::Printf("MT:D %d %x %O",NTickCount(),this,this));
+#ifdef BTRACE_CHUNKS
+	BTraceContext4(BTrace::EChunks,BTrace::EChunkDestroyed,this);
+#endif
+	}
+
+
+TInt DMemModelChunk::Close(TAny* aPtr)
+	{
+	if (aPtr)
+		{
+		DMemModelProcess* pP=(DMemModelProcess*)aPtr;
+		__NK_ASSERT_DEBUG(!iOwningProcess || iOwningProcess==pP);
+		pP->RemoveChunk(this);
+		}	
+	TInt r=Dec();
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::Close %d %O",r,this));
+	__NK_ASSERT_DEBUG(r > 0); // Should never be negative.
+	if (r==1)
+		{
+		K::ObjDelete(this);
+		return EObjectDeleted;
+		}
+	return 0;
+	}
+
+
+void DMemModelChunk::SetPaging(TUint aCreateAtt)
+	{
+	// Only user data chunks should be able to be data paged, i.e. only those 
+	// that can be created via the RChunk create methods.
+	if ((iChunkType != EUserData && iChunkType != EUserSelfModCode) ||
+		!(K::MemModelAttributes & EMemModelAttrDataPaging))	// Data paging device installed?
+		{
+		return;
+		}
+	// Pageable chunks must own their memory.
+	__NK_ASSERT_DEBUG(!(iAttributes & EMemoryNotOwned));
+
+	// Set the data paging attributes
+	TUint dataPolicy = TheSuperPage().KernelConfigFlags() & EKernelConfigDataPagingPolicyMask;
+	if (dataPolicy == EKernelConfigDataPagingPolicyNoPaging)
+		{
+		return;
+		}
+	if (dataPolicy == EKernelConfigDataPagingPolicyAlwaysPage)
+		{
+		iAttributes |= EDataPaged;
+		return;
+		}
+	TUint pagingAtt = aCreateAtt & TChunkCreate::EPagingMask;
+	if (pagingAtt == TChunkCreate::EPaged)
+		{
+		iAttributes |= EDataPaged;
+		return;
+		}
+	if (pagingAtt == TChunkCreate::EUnpaged)
+		{
+		return;
+		}
+	// No data paging attribute specified for this chunk so use the process's
+	__NK_ASSERT_DEBUG(pagingAtt == TChunkCreate::EPagingUnspec);
+	DProcess* currentProcess = TheCurrentThread->iOwningProcess;
+	if (currentProcess->iAttributes & DProcess::EDataPaged)
+		{
+		iAttributes |= EDataPaged;
+		}
+	}
+
+
+TInt DMemModelChunk::DoCreate(SChunkCreateInfo& aInfo)
+	{
+	__ASSERT_COMPILE(!(EMMChunkAttributesMask & EChunkAttributesMask));
+	__KTRACE_OPT(KMMU,Kern::Printf("Chunk %O DoCreate att=%08x",this,iAttributes));
+	if (aInfo.iMaxSize<=0)
+		return KErrArgument;
+
+	iMaxSize = MM::RoundToPageSize(aInfo.iMaxSize);
+
+	TInt maxpages=iMaxSize>>KPageShift;
+	if (iAttributes & EDisconnected)
+		{
+		TBitMapAllocator* pM=TBitMapAllocator::New(maxpages,ETrue);
+		if (!pM)
+			return KErrNoMemory;
+		iPageBitMap=pM;
+		__KTRACE_OPT(KMMU,Kern::Printf("PageBitMap at %08x, MaxPages %d",pM,maxpages));
+		}
+	if(iChunkType==ESharedKernelSingle || iChunkType==ESharedKernelMultiple)
+		{
+		TBitMapAllocator* pM=TBitMapAllocator::New(maxpages,ETrue);
+		if (!pM)
+			return KErrNoMemory;
+		iPermanentPageBitMap = pM;
+		}
+
+	TMemoryAttributes attr = EMemoryAttributeStandard;
+	TBool mapInKernel = false;
+	TBool nowipe = false;
+	TBool executable = false;
+	TBool movable = false;
+	TInt r;
+
+	switch(iChunkType)
+		{
+	case EUserSelfModCode:
+		executable = true;
+		movable = true;
+		break;
+
+	case EUserData:
+	case ERamDrive:
+		movable = true;
+		break;
+
+	case EKernelMessage:
+	case ESharedKernelSingle:
+	case ESharedKernelMultiple:
+	case ESharedIo:
+		mapInKernel = true;
+		r = MM::MemoryAttributes(attr,*(TMappingAttributes2*)&aInfo.iMapAttr);
+		if(r!=KErrNone)
+			return r;
+		break;
+
+	case EKernelData:
+		nowipe = true;
+		break;
+
+	case EDllData:
+		__NK_ASSERT_DEBUG(0); // invalid chunk type
+	case EKernelStack:
+		__NK_ASSERT_DEBUG(0); // invalid chunk type
+	case EDll: // global code
+		__NK_ASSERT_DEBUG(0); // invalid chunk type
+	case EKernelCode:
+		__NK_ASSERT_DEBUG(0); // invalid chunk type
+	case EUserCode: // local code
+		__NK_ASSERT_DEBUG(0); // invalid chunk type
+	case ESharedKernelMirror:
+		__NK_ASSERT_DEBUG(0); // invalid chunk type
+	default:
+		__NK_ASSERT_DEBUG(0); // invalid chunk type
+		return KErrArgument;
+		}
+
+	// calculate memory type...
+	TMemoryObjectType memoryType = EMemoryObjectUnpaged;
+	if (iAttributes & EMemoryNotOwned)
+		{
+		if (memoryType != EMemoryObjectUnpaged)
+			return KErrArgument;
+		memoryType = EMemoryObjectHardware;
+		}
+	if (iAttributes & EDataPaged)
+		{
+		if (memoryType != EMemoryObjectUnpaged)
+			return KErrArgument;
+		memoryType = EMemoryObjectPaged;
+		}
+	if (iAttributes & ECache)
+		{
+		if (memoryType != EMemoryObjectUnpaged)
+			return KErrArgument;
+		memoryType = EMemoryObjectDiscardable;
+		}
+	if (memoryType == EMemoryObjectUnpaged)
+		{
+		if (movable)
+			memoryType = EMemoryObjectMovable;
+		}
+
+	// calculate memory flags...
+	TMemoryCreateFlags flags = nowipe ? EMemoryCreateNoWipe : EMemoryCreateDefault;
+	flags = (TMemoryCreateFlags)(flags|EMemoryCreateUseCustomWipeByte|(iClearByte<<EMemoryCreateWipeByteShift));
+	if(executable)
+		flags = (TMemoryCreateFlags)(flags|EMemoryCreateAllowExecution);
+
+	r = MM::MemoryNew(iMemoryObject,memoryType,MM::BytesToPages(iMaxSize),flags,attr);
+	if(r!=KErrNone)
+		return r;
+
+	if(mapInKernel)
+		{
+		TInt r = MM::MappingNew(iKernelMapping, iMemoryObject, ESupervisorReadWrite, KKernelOsAsid);
+		if(r!=KErrNone)
+			return r; // Note, iMemoryObject will get cleaned-up when chunk is destroyed
+		const TMappingAttributes2& lma = MM::LegacyMappingAttributes(attr,EUserReadWrite);
+		*(TMappingAttributes2*)&iMapAttr = lma;
+		}
+
+#ifdef BTRACE_CHUNKS
+	TKName nameBuf;
+	Name(nameBuf);
+	BTraceContextN(BTrace::EChunks,BTrace::EChunkCreated,this,iMaxSize,nameBuf.Ptr(),nameBuf.Size());
+	if(iOwningProcess)
+		BTrace8(BTrace::EChunks,BTrace::EChunkOwner,this,iOwningProcess);
+	BTraceContext12(BTrace::EChunks,BTrace::EChunkInfo,this,iChunkType,iAttributes);
+#endif
+#ifdef BTRACE_FLEXIBLE_MEM_MODEL
+	BTrace8(BTrace::EFlexibleMemModel,BTrace::EMemoryObjectIsChunk,iMemoryObject,this);
+#endif
+	return KErrNone;
+	}
+
+
+void DMemModelChunk::SetFixedAddress(TLinAddr aAddr, TInt aInitialSize)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk %O SetFixedAddress %08x size %08x",this,aAddr,aInitialSize));
+	iFixedBase = aAddr;
+	iSize = MM::RoundToPageSize(aInitialSize);
+	if(iSize)
+		MM::MemoryClaimInitialPages(iMemoryObject,iFixedBase,iSize,ESupervisorReadWrite);
+	}
+
+
+TInt DMemModelChunk::SetAttributes(SChunkCreateInfo& aInfo)
+	{
+	switch(iChunkType)
+		{
+		case EKernelData:
+		case EKernelMessage:
+			iAttributes = EPrivate;
+			break;
+		case ERamDrive:
+			iAttributes = EPrivate;
+			break;
+		case EUserData:
+			if (aInfo.iGlobal)
+				iAttributes = EPublic;
+			else
+				iAttributes = EPrivate;
+			break;
+		case EUserSelfModCode:
+			if (aInfo.iGlobal)
+				iAttributes = EPublic|ECode;
+			else
+				iAttributes = EPrivate|ECode;
+			break;
+		case ESharedKernelSingle:
+		case ESharedKernelMultiple:
+		case ESharedIo:
+			iAttributes = EPublic;
+			break;
+		case EDllData:
+			__NK_ASSERT_DEBUG(0); // invalid chunk type
+		case EKernelStack:
+			__NK_ASSERT_DEBUG(0); // invalid chunk type
+		case EDll: // global code
+			__NK_ASSERT_DEBUG(0); // invalid chunk type
+		case EKernelCode:
+			__NK_ASSERT_DEBUG(0); // invalid chunk type
+		case EUserCode: // local code
+			__NK_ASSERT_DEBUG(0); // invalid chunk type
+		case ESharedKernelMirror:
+			__NK_ASSERT_DEBUG(0); // invalid chunk type
+		default:
+			FAULT();
+		}
+	return KErrNone;
+	}
+
+
+TInt DMemModelChunk::Adjust(TInt aNewSize)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::Adjust %08x",aNewSize));
+	if (iAttributes & (EDoubleEnded|EDisconnected))
+		return KErrGeneral;
+	if (aNewSize<0 || aNewSize>iMaxSize)
+		return KErrArgument;
+
+	TInt r=KErrNone;
+	TInt newSize=MM::RoundToPageSize(aNewSize);
+	if (newSize!=iSize)
+		{
+		MM::MemoryLock(iMemoryObject);
+		if (newSize>iSize)
+			{
+			__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::Adjust growing"));
+			r=DoCommit(iSize,newSize-iSize);
+			}
+		else if (newSize<iSize)
+			{
+			__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::Adjust shrinking"));
+			DoDecommit(newSize,iSize-newSize);
+			}
+		MM::MemoryUnlock(iMemoryObject);
+		}
+	__COND_DEBUG_EVENT(r==KErrNone, EEventUpdateChunk, this);
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk %O adjusted to %x",this,iSize));
+	return r;
+	}
+
+
+TInt DMemModelChunk::Address(TInt aOffset, TInt aSize, TLinAddr& aKernelAddress)
+	{
+	if(!iPermanentPageBitMap)
+		return KErrAccessDenied;
+	if(TUint(aOffset)>=TUint(iMaxSize))
+		return KErrArgument;
+	if(TUint(aOffset+aSize)>TUint(iMaxSize))
+		return KErrArgument;
+	if(aSize<=0)
+		return KErrArgument;
+	TInt start = aOffset>>KPageShift;
+	TInt size = ((aOffset+aSize-1)>>KPageShift)-start+1;
+	if(iPermanentPageBitMap->NotAllocated(start,size))
+		return KErrNotFound;
+	aKernelAddress = MM::MappingBase(iKernelMapping)+aOffset;
+	return KErrNone;
+	}
+
+
+TInt DMemModelChunk::PhysicalAddress(TInt aOffset, TInt aSize, TLinAddr& aKernelAddress, TUint32& aPhysicalAddress, TUint32* aPhysicalPageList)
+	{
+	if(aSize<=0)
+		return KErrArgument;
+	TInt r = Address(aOffset,aSize,aKernelAddress);
+	if(r!=KErrNone)
+		return r;
+	TInt index = aOffset>>KPageShift;
+	TInt count = ((aOffset+aSize-1)>>KPageShift)-index+1;
+	r = MM::MemoryPhysAddr(iMemoryObject,index,count,aPhysicalAddress,aPhysicalPageList);
+	if(r==KErrNone)
+		aPhysicalAddress += aOffset&KPageMask;
+	return r;
+	}
+
+
+TInt DMemModelChunk::DoCommit(TInt aOffset, TInt aSize, TCommitType aCommitType, TUint32* aExtraArg)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::DoCommit %x+%x type=%d extra=%08x",aOffset,aSize,aCommitType,aExtraArg));
+
+	__NK_ASSERT_DEBUG(((aOffset|aSize)&KPageMask)==0);
+
+	TInt r = KErrArgument;
+	switch(aCommitType)
+		{
+	case DChunk::ECommitDiscontiguous:
+		r = MM::MemoryAlloc(iMemoryObject, MM::BytesToPages(aOffset), MM::BytesToPages(aSize));
+		break;
+
+	case DChunk::ECommitDiscontiguousPhysical:
+		r = MM::MemoryAddPages(iMemoryObject, MM::BytesToPages(aOffset), MM::BytesToPages(aSize), (TPhysAddr*)aExtraArg);
+		break;
+
+	case DChunk::ECommitContiguous:
+		r = MM::MemoryAllocContiguous(iMemoryObject, MM::BytesToPages(aOffset), MM::BytesToPages(aSize), 0, *(TPhysAddr*)aExtraArg);
+		break;
+
+	case DChunk::ECommitContiguousPhysical:
+		r = MM::MemoryAddContiguous(iMemoryObject, MM::BytesToPages(aOffset), MM::BytesToPages(aSize), (TPhysAddr)aExtraArg);
+		break;
+
+	case DChunk::ECommitVirtual:
+	default:
+		__NK_ASSERT_DEBUG(0); // Invalid commit type
+		r = KErrNotSupported;
+		break;
+		}
+
+	if(r==KErrNone)
+		{
+		iSize += aSize;
+		if(iPermanentPageBitMap)
+			iPermanentPageBitMap->Alloc(aOffset>>KPageShift,aSize>>KPageShift);
+#ifdef BTRACE_CHUNKS
+		TInt subcategory = (aCommitType & DChunk::ECommitPhysicalMask) ? BTrace::EChunkMemoryAdded : BTrace::EChunkMemoryAllocated;
+		BTraceContext12(BTrace::EChunks,subcategory,this,aOffset,aSize);
+#endif
+		}
+
+	return r;
+	}
+
+
+void DMemModelChunk::DoDecommit(TInt aOffset, TInt aSize)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::DoDecommit %x+%x",aOffset,aSize));
+
+	__NK_ASSERT_DEBUG(((aOffset|aSize)&KPageMask)==0);
+
+	TUint index = MM::BytesToPages(aOffset);
+	TUint count = MM::BytesToPages(aSize);
+	iSize -= count*KPageSize;
+	if(iAttributes&EMemoryNotOwned)
+		MM::MemoryRemovePages(iMemoryObject, index, count, 0);
+	else
+		MM::MemoryFree(iMemoryObject, index, count);
+
+#ifdef BTRACE_CHUNKS
+	if (count != 0)
+		{
+		TInt subcategory = (iAttributes & EMemoryNotOwned) ? BTrace::EChunkMemoryRemoved : BTrace::EChunkMemoryDeallocated;
+		BTraceContext12(BTrace::EChunks,subcategory,this,aOffset,count*KPageSize);
+		}
+#endif
+	}
+
+
+TInt DMemModelChunk::AdjustDoubleEnded(TInt aBottom, TInt aTop)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::AdjustDoubleEnded %x-%x",aBottom,aTop));
+	if ((iAttributes & (EDoubleEnded|EDisconnected))!=EDoubleEnded)
+		return KErrGeneral;
+	if (aTop<0 || aBottom<0 || aTop<aBottom || aTop>iMaxSize)
+		return KErrArgument;
+
+	aBottom &= ~KPageMask;
+	aTop = MM::RoundToPageSize(aTop);
+	TInt newSize=aTop-aBottom;
+	if (newSize>iMaxSize)
+		return KErrArgument;
+
+	MM::MemoryLock(iMemoryObject);
+	TInt initBottom=iStartPos;
+	TInt initTop=iStartPos+iSize;
+	TInt nBottom=Max(aBottom,iStartPos);	// intersection bottom
+	TInt nTop=Min(aTop,iStartPos+iSize);	// intersection top
+	TInt r=KErrNone;
+	if (nBottom<nTop)
+		{
+		__KTRACE_OPT(KMMU,Kern::Printf("Initial and final regions intersect"));
+		if (initBottom<nBottom)
+			{
+			iStartPos=aBottom;
+			DoDecommit(initBottom,nBottom-initBottom);
+			}
+		if (initTop>nTop)
+			DoDecommit(nTop,initTop-nTop);	// this changes iSize
+		if (aBottom<nBottom)
+			{
+			r=DoCommit(aBottom,nBottom-aBottom);
+			if (r==KErrNone)
+				{
+				if (aTop>nTop)
+					r=DoCommit(nTop,aTop-nTop);
+				if (r==KErrNone)
+					iStartPos=aBottom;
+				else
+					DoDecommit(aBottom,nBottom-aBottom);
+				}
+			}
+		else if (aTop>nTop)
+			r=DoCommit(nTop,aTop-nTop);
+		}
+	else
+		{
+		__KTRACE_OPT(KMMU,Kern::Printf("Initial and final regions disjoint"));
+		if (iSize)
+			DoDecommit(initBottom,iSize);
+		iStartPos=aBottom;
+		if (newSize)
+			r=DoCommit(iStartPos,newSize);
+		}
+	MM::MemoryUnlock(iMemoryObject);
+	__COND_DEBUG_EVENT(r==KErrNone, EEventUpdateChunk, this);
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk %O adjusted to %x+%x",this,iStartPos,iSize));
+	return r;
+	}
+
+
+TInt DMemModelChunk::CheckRegion(TInt& aOffset, TInt& aSize)
+	{
+	if((iAttributes & (EDoubleEnded|EDisconnected))!=EDisconnected)
+		return KErrGeneral;
+	if(aOffset<0 || aSize<0)
+		return KErrArgument;
+	if(aSize==0)
+		return KErrNone;
+
+	TUint end = MM::RoundToPageSize(aOffset+aSize);
+	if(end>TUint(iMaxSize))
+		return KErrArgument;
+	aOffset &= ~KPageMask;
+	aSize = end-aOffset;
+	if(end<=TUint(aOffset))
+		return KErrArgument;
+
+	return 1;
+	}
+
+
+TInt DMemModelChunk::Commit(TInt aOffset, TInt aSize, TCommitType aCommitType, TUint32* aExtraArg)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::Commit %x+%x type=%d extra=%08x",aOffset,aSize,aCommitType,aExtraArg));
+
+	TInt r = CheckRegion(aOffset,aSize);
+	if(r<=0)
+		return r;
+
+	MM::MemoryLock(iMemoryObject);
+	TInt i=aOffset>>KPageShift;
+	TInt n=aSize>>KPageShift;
+	if (iPageBitMap->NotFree(i,n))
+		r=KErrAlreadyExists;
+	else
+		{
+		r=DoCommit(aOffset,aSize,aCommitType,aExtraArg);
+		if (r==KErrNone)
+			iPageBitMap->Alloc(i,n);
+		}
+	MM::MemoryUnlock(iMemoryObject);
+	__COND_DEBUG_EVENT(r==KErrNone, EEventUpdateChunk, this);
+	return r;
+	}
+
+
+TInt DMemModelChunk::Allocate(TInt aSize, TInt aGuard, TInt aAlign)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::Allocate %x %x %d",aSize,aGuard,aAlign));
+
+	// the flexible memory model doesn't implement aGuard and aAlign...
+	__NK_ASSERT_DEBUG(aGuard==0);
+	(void)aGuard;
+	__NK_ASSERT_DEBUG(aAlign==0);
+	(void)aAlign;
+
+	TInt dummyOffset = 0;
+	TInt r = CheckRegion(dummyOffset,aSize);
+	if(r<=0)
+		return r;
+
+	MM::MemoryLock(iMemoryObject);
+	TInt n=aSize>>KPageShift;
+	TInt i=iPageBitMap->AllocConsecutive(n, EFalse);		// allocate the offset
+	if (i<0)
+		r=KErrNoMemory;		// run out of reserved space for this chunk
+	else
+		{
+		TInt offset=i<<KPageShift;
+		__KTRACE_OPT(KMMU,Kern::Printf("Offset %x allocated",offset));
+		r=DoCommit(offset,aSize);
+		if (r==KErrNone)
+			{
+			iPageBitMap->Alloc(i,n);
+			r=offset;		// if operation successful, return allocated offset
+			}
+		}
+	MM::MemoryUnlock(iMemoryObject);
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::Allocate returns %x",r));
+	__COND_DEBUG_EVENT(r==KErrNone, EEventUpdateChunk, this);
+	return r;
+	}
+
+
+TInt DMemModelChunk::Decommit(TInt aOffset, TInt aSize)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::Decommit %x+%x",aOffset,aSize));
+	TInt r = CheckRegion(aOffset,aSize);
+	if(r<=0)
+		return r;
+
+	MM::MemoryLock(iMemoryObject);
+
+	TInt i=aOffset>>KPageShift;
+	TInt n=aSize>>KPageShift;
+	__KTRACE_OPT(KMMU,Kern::Printf("Calling SelectiveFree(%d,%d)",i,n));
+
+	TUint oldAvail = iPageBitMap->iAvail;
+	iPageBitMap->SelectiveFree(i,n);	// free those positions which are actually allocated
+	TUint oldSize = iSize;
+
+	DoDecommit(aOffset,aSize);
+
+	// Use the bit map to adjust the size of the chunk as unlocked and reclaimed pages
+	// will have been unmapped but not removed from the bit map as DoDecommit() only 
+	// decommits the mapped pages.
+	TUint actualFreedPages = iPageBitMap->iAvail - oldAvail;
+	iSize = oldSize - (actualFreedPages << KPageShift);
+
+	MM::MemoryUnlock(iMemoryObject);
+
+	r=KErrNone;
+	__COND_DEBUG_EVENT(r==KErrNone, EEventUpdateChunk, this);
+	return r;
+	}
+
+
+TInt DMemModelChunk::Unlock(TInt aOffset, TInt aSize)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::Unlock %x+%x",aOffset,aSize));
+	if(!(iAttributes&ECache))
+		return KErrGeneral;
+	TInt r = CheckRegion(aOffset,aSize);
+	if(r<=0)
+		return r;
+
+	MM::MemoryLock(iMemoryObject);
+
+	TInt i=aOffset>>KPageShift;
+	TInt n=aSize>>KPageShift;
+	if(iPageBitMap->NotAllocated(i,n))
+		r = KErrNotFound;
+	else
+		r = MM::MemoryAllowDiscard(iMemoryObject,i,n);
+
+	MM::MemoryUnlock(iMemoryObject);
+
+	return r;
+	}
+
+
+TInt DMemModelChunk::Lock(TInt aOffset, TInt aSize)
+	{
+	__KTRACE_OPT(KMMU,Kern::Printf("DMemModelChunk::Lock %x+%x",aOffset,aSize));
+	if(!(iAttributes&ECache))
+		return KErrGeneral;
+	TInt r = CheckRegion(aOffset,aSize);
+	if(r<=0)
+		return r;
+
+	r = MM::MemoryDisallowDiscard(iMemoryObject, MM::BytesToPages(aOffset), MM::BytesToPages(aSize));
+	if(r!=KErrNone)
+		Decommit(aOffset,aSize);
+
+	return r;
+	}
+
+
+TInt DMemModelChunk::CheckAccess()
+	{
+	if(iOwningProcess && iOwningProcess!=TheCurrentThread->iOwningProcess)
+		return KErrAccessDenied;
+	return KErrNone;
+	}
+
+
+void DMemModelChunk::BTracePrime(TInt aCategory)
+	{
+	DChunk::BTracePrime(aCategory);
+#ifdef BTRACE_FLEXIBLE_MEM_MODEL
+	if (aCategory == BTrace::EFlexibleMemModel || aCategory == -1)
+		{
+		if (iMemoryObject)
+			{
+			MM::MemoryBTracePrime(iMemoryObject);
+			BTrace8(BTrace::EFlexibleMemModel,BTrace::EMemoryObjectIsChunk,iMemoryObject,this);
+			}
+		}
+#endif
+	}
+
+
+void DMemModelChunk::Substitute(TInt /*aOffset*/, TPhysAddr /*aOldAddr*/, TPhysAddr /*aNewAddr*/)
+	{
+	MM::Panic(MM::EUnsupportedOperation);
+	}
+