--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/kernel/eka/memmodel/epoc/flexible/mmu/mpagearray.cpp	Mon Oct 19 15:55:17 2009 +0100
@@ -0,0 +1,1349 @@
+// Copyright (c) 2007-2009 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 <plat_priv.h>
+#include "mm.h"
+#include "mmu.h"
+
+#include "mpagearray.h"
+#include "mslaballoc.h"
+
+
+static RStaticSlabAllocator<RPageArray::TSegment,KPageArraySegmentBase,KPageArraySegmentEnd> PageSegmentAllocator;
+
+
+//
+// RPageArray::TSegment
+//
+
+RPageArray::TSegment* RPageArray::TSegment::New()
+	{
+	__NK_ASSERT_DEBUG(!MmuLock::IsHeld());
+
+	// allocate segment...
+	TSegment* s = PageSegmentAllocator.Alloc();
+	if(!s)
+		return s;
+
+	// initialise segment...
+	s->iCounts = 1; // lock count = 1, alloc count = 0
+	TPhysAddr* p = s->iPages;
+	TPhysAddr* pEnd = p+KPageArraySegmentSize;
+	TPhysAddr nullPage = EEmptyEntry;
+	do *p++ = nullPage;
+	while(p<pEnd);
+
+	return s;
+	}
+
+
+RPageArray::TSegment* RPageArray::TSegment::Delete(TSegment* aSegment)
+	{
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	__NK_ASSERT_DEBUG(aSegment->iCounts==0);
+#ifdef _DEBUG
+	TPhysAddr* p = aSegment->iPages;
+	TPhysAddr* pEnd = p+KPageArraySegmentSize;
+	do
+		{
+		TPhysAddr a = *p++;
+		if(IsPresent(a))
+			{
+			Kern::Printf("TSegment Delete with allocated pages! [%d]=0x%08x",p-aSegment->iPages-1,a);
+			__NK_ASSERT_DEBUG(0);
+			}
+		}
+	while(p<pEnd);
+#endif
+	PageSegmentAllocator.Free(aSegment);
+	return 0;
+	}
+
+
+FORCE_INLINE void RPageArray::TSegment::Lock(TUint aCount)
+	{
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	__e32_atomic_add_ord32(&iCounts, (TUint32)aCount);
+	__NK_ASSERT_DEBUG((iCounts&KPageArraySegmentLockCountMask));
+	}
+
+
+/**
+@return True if segment still exists, false if segment was deleted.
+*/
+TBool RPageArray::TSegment::Unlock(TSegment*& aSegment, TUint aCount)
+	{
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+
+	TSegment* s = aSegment;
+	__NK_ASSERT_DEBUG(s);
+
+	TUint oldCounts = (TUint)__e32_atomic_add_ord32(&s->iCounts, (TUint32)-(TInt)aCount);
+	__NK_ASSERT_DEBUG(oldCounts&KPageArraySegmentLockCountMask); // alloc count must have been non-zero before decrementing
+
+#ifdef _DEBUG
+	if((oldCounts&KPageArraySegmentLockCountMask)==aCount)
+		{
+		// check alloc count is consistent...
+		TUint allocCount = s->iCounts>>KPageArraySegmentAllocCountShift;
+		__NK_ASSERT_DEBUG(allocCount<=KPageArraySegmentSize);
+		TUint realAllocCount = 0;
+		TPhysAddr* p = s->iPages;
+		TPhysAddr* pEnd = p+KPageArraySegmentSize;
+		do
+			{
+			if(IsPresent(*p++))
+				++realAllocCount;
+			}
+		while(p<pEnd);
+		if(realAllocCount!=allocCount)
+			{
+			Kern::Printf("TSegment::Unlock alloc count missmatch %u!=%u",realAllocCount,allocCount);
+			__NK_ASSERT_DEBUG(0);
+			}
+		}
+#endif
+
+	if(oldCounts>1)
+		return oldCounts; // return 'true' to indicate segment still exists
+
+	// delete segment...
+	aSegment = 0;
+	return (TBool)Delete(s); // returns 'false'
+	}
+
+
+FORCE_INLINE void RPageArray::TSegment::AdjustAllocCount(TInt aDelta)
+	{
+	__NK_ASSERT_DEBUG((iCounts&KPageArraySegmentLockCountMask));
+	__e32_atomic_add_ord32(&iCounts, TUint32(aDelta)<<KPageArraySegmentAllocCountShift);
+	}
+
+
+#ifdef _DEBUG
+void RPageArray::TSegment::Dump()
+	{
+	TUint allocCount = iCounts>>KPageArraySegmentAllocCountShift;
+	TUint lockCount = iCounts&KPageArraySegmentLockCountMask;
+	Kern::Printf("RPageArray::TSegment[0x%08x]::Dump() allocCount=%d lockCount=%d",this,allocCount,lockCount);
+	for(TUint i=0; i<KPageArraySegmentSize; i+=4)
+		Kern::Printf("  %08x %08x %08x %08x",iPages[i+0],iPages[i+1],iPages[i+2],iPages[i+3]);
+	}
+#endif
+
+
+//
+// RPageArray::TIter
+//
+
+TUint RPageArray::TIter::Pages(TPhysAddr*& aStart, TUint aMaxCount)
+	{
+	// MmuLock *may* be needed, depends if segments have been locked
+
+	TUint index = iIndex;
+	TUint size = iEndIndex-index;
+	if(!size)
+		return 0;
+
+	TUint offset = index&KPageArraySegmentMask;
+	aStart = iSegments[index>>KPageArraySegmentShift]->iPages+offset;
+
+	TUint n = KPageArraySegmentSize-offset;
+	if(n>aMaxCount)
+		n = aMaxCount;
+	if(n>size)
+		n = size;
+	return n;
+	}
+
+
+TUint RPageArray::TIter::AddFind(TIter& aPageList)
+	{
+	TRACE2(("RPageArray::TIter::AddFind range 0x%x..0x%x",iIndex,iEndIndex));
+
+	TUint index = iIndex;
+	TUint endIndex = iEndIndex;
+	if(index==endIndex)
+		{
+nothing_found:
+		aPageList.iIndex = endIndex;
+		aPageList.iEndIndex = endIndex;
+		TRACE2(("RPageArray::TIter::AddFind returns 0x%x+0x%x",iEndIndex,0));
+		return 0;
+		}
+
+	TSegment** pS = iSegments+(index>>KPageArraySegmentShift);
+	TPhysAddr* p;
+	TUint limit;
+
+	MmuLock::Lock();
+
+	// scan for empty entries...
+	do
+		{
+		// get segment...
+		p = (*pS++)->iPages+(index&KPageArraySegmentMask);
+		TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+		limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+		// scan segment...
+		do
+			{
+			TPhysAddr page = *p;
+			if(!IsPresent(page))
+				goto find_start;
+#if _DEBUG
+			if(State(page)!=ECommitted)
+				{
+				Kern::Printf("RPageArray::TIter::AddFind found unexpected page: %x",page);
+				__NK_ASSERT_DEBUG(0);
+				// *p = (page&~(EStateMask|EVetoed))|ECommitted; // mark page as allocated again
+				}
+#endif
+			++p;
+			}
+		while(++index<limit);
+
+		MmuLock::Flash();
+		}
+	while(index<endIndex);
+
+	MmuLock::Unlock();
+	goto nothing_found;
+
+find_start:
+	TUint startIndex = index;
+	// scan for end of empty region...
+	for(;;)
+		{
+		// scan segment...
+		do
+			{
+			if(IsPresent(*p++))
+				goto find_end;
+			}
+		while(++index<limit);
+		// check for end...
+		if(index>=endIndex)
+			break;
+		MmuLock::Flash();
+		// get next segment...
+		p = (*pS++)->iPages;
+		TUint nextIndex = index+KPageArraySegmentSize;
+		limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+		}
+
+find_end:
+	MmuLock::Unlock();
+
+	aPageList.iSegments = iSegments;
+	aPageList.iIndex = startIndex;
+	aPageList.iEndIndex = index;
+
+	iIndex = index;
+	TUint n = index-startIndex;
+	TRACE2(("RPageArray::TIter::AddFind returns 0x%x+0x%x",startIndex,n));
+	return n;
+	}
+
+
+void RPageArray::TIter::Add(TUint aCount, TPhysAddr* aPages)
+	{
+	// MmuLock NOT required because...
+	// 1. AddStart has ensured all segments are allocated and locked (so they can't be deleted)
+	// 2. AddFind returns an unallocated region. This can only be changed by Adding pages
+	//    and we only allow one thread to do this at a time (i.e. the thread calling this function.)
+
+	TRACE2(("RPageArray::TIter::Add 0x%x+0x%x",iIndex,aCount));
+	__NK_ASSERT_DEBUG(aCount);
+
+	TUint index = iIndex;
+	TUint endIndex = index+aCount;
+	TSegment** pS = iSegments+(index>>KPageArraySegmentShift);
+	do
+		{
+		// get segment...
+		TSegment* s = *pS++;
+		TPhysAddr* p = s->iPages+(index&KPageArraySegmentMask);
+		TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+		TUint limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+
+		// add pages to segment...
+		s->AdjustAllocCount(limit-index);
+		do
+			{
+			__NK_ASSERT_DEBUG((*aPages&KPageMask)==0);
+			__NK_ASSERT_DEBUG(!IsPresent(*p)); // AddFind only found not-present entries
+			*p++ = *aPages++|ECommitted;
+			}
+		while(++index<limit);
+		}
+	while(index<endIndex);
+
+	iIndex = index;
+	}
+
+
+void RPageArray::TIter::AddContiguous(TUint aCount, TPhysAddr aPhysAddr)
+	{
+	// MmuLock NOT required because...
+	// 1. AddStart has ensured all segments are allocated and locked (so they can't be deleted)
+	// 2. AddFind returns an unallocated region. This can only be changed by Adding pages
+	//    and we only allow one thread to do this at a time (i.e. the thread calling this function.)
+
+	TRACE2(("RPageArray::TIter::AddContiguous 0x%x+0x%x",iIndex,aCount));
+	__NK_ASSERT_DEBUG(aCount);
+	__NK_ASSERT_DEBUG((aPhysAddr&KPageMask)==0);
+
+	TUint index = iIndex;
+	TUint endIndex = index+aCount;
+	TSegment** pS = iSegments+(index>>KPageArraySegmentShift);
+
+	do
+		{
+		// get segment...
+		TSegment* s = *pS++;
+		TPhysAddr* p = s->iPages+(index&KPageArraySegmentMask);
+		TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+		TUint limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+
+		// add pages to segment...
+		s->AdjustAllocCount(limit-index);
+		do
+			{
+			__NK_ASSERT_DEBUG(!IsPresent(*p)); // AddFind only found not-present entries
+			*p++ = aPhysAddr|ECommitted;
+			aPhysAddr += KPageSize;
+			}
+		while(++index<limit);
+		}
+	while(index<endIndex);
+
+	iIndex = index;
+	}
+
+
+void RPageArray::TIter::Added(TUint aCount, TUint aChanged)
+	{
+	__NK_ASSERT_DEBUG(aCount);
+	__NK_ASSERT_DEBUG(aChanged<=aCount);
+	TUint index = iIndex;
+	__NK_ASSERT_DEBUG((index>>KPageArraySegmentShift)==((index+aCount-1)>>KPageArraySegmentShift));
+	TSegment* s = iSegments[index>>KPageArraySegmentShift];
+	__NK_ASSERT_DEBUG(s);
+	__NK_ASSERT_DEBUG(s->iCounts&KPageArraySegmentLockCountMask);
+	s->AdjustAllocCount(aChanged);
+	Skip(aCount);
+	}
+
+
+TUint RPageArray::TIter::Find(TIter& aPageList)
+	{
+	TRACE2(("RPageArray::TIter::Find range 0x%x..0x%x",iIndex,iEndIndex));
+
+	MmuLock::Lock();
+	TUint index = iIndex;
+	TUint endIndex = iEndIndex;
+	TSegment** pS = iSegments+(index>>KPageArraySegmentShift);
+	TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+
+	// search for first page...
+	while(index<endIndex)
+		{
+		TSegment* s = *pS;
+		if(!s)
+			index = nextIndex;
+		else
+			{
+			// search segment...
+			TPhysAddr* p = s->iPages+(index&KPageArraySegmentMask);
+			TUint limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+			do
+				{
+				if(RPageArray::IsPresent(*p++))
+					goto start_done;
+				}
+			while(++index<limit);
+			}
+		// next segment...
+		MmuLock::Flash();
+		++pS;
+		nextIndex = index+KPageArraySegmentSize;
+		}
+start_done:
+	// we can't flash or release the MmuLock until we've Locked the segment we found!
+	iIndex = index;
+
+	// search for range of allocated pages...
+	while(index<endIndex)
+		{
+		// check first entry...
+		TSegment* s = *pS;
+		if(!s)
+			break;
+		TPhysAddr* p = s->iPages+(index&KPageArraySegmentMask);
+		if(!RPageArray::IsPresent(*p++))
+			break;
+
+		// segment has pages, lock it...
+		s->Lock();
+
+		// scan rest of entries...
+		TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+		TUint limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+		while(++index<limit)
+			if(!RPageArray::IsPresent(*p++))
+				goto done;
+
+		// next segment...
+		MmuLock::Flash();
+		++pS;
+		}
+done:
+	MmuLock::Unlock();
+
+	aPageList.iSegments = iSegments;
+	aPageList.iIndex = iIndex;
+	aPageList.iEndIndex = index;
+	TInt n = index-iIndex;
+	TRACE2(("RPageArray::TIter::Find returns 0x%x+0x%x",iIndex,n));
+	return n;
+	}
+
+
+void RPageArray::TIter::FindRelease(TUint aCount)
+	{
+	TUint index = iIndex;
+	Skip(aCount);
+	RPageArray::Release(iSegments,index,aCount);
+	}
+
+
+TUint RPageArray::TIter::RemoveFind(TIter& aPageList)
+	{
+	TRACE2(("RPageArray::TIter::RemoveFind range 0x%x..0x%x",iIndex,iEndIndex));
+
+	MmuLock::Lock();
+
+	TUint index = iIndex;
+	TUint endIndex = iEndIndex;
+	TSegment** pS = iSegments+(index>>KPageArraySegmentShift);
+	TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+
+	// search for first page...
+	while(index<endIndex)
+		{
+		TSegment* s = *pS;
+		if(!s)
+			index = nextIndex;
+		else
+			{
+			// search segment...
+			TPhysAddr* p = s->iPages+(index&KPageArraySegmentMask);
+			TUint limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+			do
+				{
+				if(State(*p++)>=EDecommitting)
+					goto start_done;
+				}
+			while(++index<limit);
+			}
+
+		// next segment...
+		MmuLock::Flash();
+		++pS;
+		nextIndex = index+KPageArraySegmentSize;
+		}
+start_done:
+	// we can't flash or release the MmuLock until we've Locked the segment we found!
+	iIndex = index;
+
+	// search for range of allocated pages, marking them EDecommitting...
+	while(index<endIndex)
+		{
+		// check first entry...
+		TSegment* s = *pS;
+		if(!s)
+			break;
+		TPhysAddr* p = s->iPages+(index&KPageArraySegmentMask);
+		TPhysAddr page = *p++;
+		if(State(page)<EDecommitting)
+			break;
+
+		p[-1] = (page&~EStateMask)|EDecommitting;
+
+		// segment has pages, lock it...
+		s->Lock();
+
+		// scan rest of entries...
+		TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+		TUint limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+		while(++index<limit)
+			{
+			TPhysAddr page = *p++;
+			if(State(page)<EDecommitting)
+				goto done;
+			p[-1] = (page&~EStateMask)|EDecommitting;
+			}
+
+		// next segment...
+		MmuLock::Flash();
+		++pS;
+		}
+done:
+	MmuLock::Unlock();
+
+	aPageList.iSegments = iSegments;
+	aPageList.iIndex = iIndex;
+	aPageList.iEndIndex = index;
+	TInt n = index-iIndex;
+	TRACE2(("RPageArray::TIter::RemoveFind returns 0x%x+0x%x",iIndex,n));
+	return n;
+	}
+
+
+TUint RPageArray::TIter::Remove(TUint aMaxCount, TPhysAddr* aPages)
+	{
+	TRACE2(("RPageArray::TIter::Remove 0x%x..0x%x max=0x%x",iIndex,iEndIndex,aMaxCount));
+
+	__NK_ASSERT_DEBUG(aMaxCount);
+
+	TUint count = 0;
+	TUint index = iIndex;
+	TUint endIndex = iEndIndex;
+	if(index==endIndex)
+		return 0;
+
+	TSegment** pS = iSegments+(index>>KPageArraySegmentShift);
+
+	MmuLock::Lock();
+
+	do
+		{
+		// get segment...
+		TSegment* s = *pS++;
+		TPhysAddr* p = s->iPages+(index&KPageArraySegmentMask);
+		TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+		TUint limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+
+		// remove pages from segment...
+		do
+			{
+			TPhysAddr page = *p++;
+			__NK_ASSERT_DEBUG(State(page)!=EStealing); // can't be stealing as that only happens with the RamAllocLock held, which we should already hold if freeing demand paged pages
+			if(State(page)==EDecommitting || State(page)==EDecommitted)
+				{
+				// remove a page...
+				if(page&EUnmapVetoed)
+					{
+					p[-1] = (page&~(EUnmapVetoed|EStateMask))|EDecommitted; // change to EDecommitted state
+					}
+				else
+					{
+					p[-1] = EEmptyEntry;
+					s->AdjustAllocCount(-1);
+					TPhysAddr pagePhys = page&~KPageMask;
+					aPages[count++] = pagePhys;
+					TRACE2(("RPageArray::TIter::Remove index=0x%x returns 0x%08x",index,pagePhys));
+					if(count>=aMaxCount)
+						{
+						++index;
+						goto done;
+						}
+					}
+				// check not removing managed pages without the RamAllocLock...
+				__NK_ASSERT_DEBUG(RamAllocLock::IsHeld()
+					|| SPageInfo::FromPhysAddr(page)->Type()!=SPageInfo::EManaged);
+				}
+			}
+		while(++index<limit);
+
+		MmuLock::Flash();
+		}
+	while(index<endIndex);
+
+done:
+	MmuLock::Unlock();
+	iIndex = index;
+	return count;
+	}
+
+
+void RPageArray::TIter::VetoUnmap()
+	{
+	TUint index = iIndex;
+	TUint endIndex = iEndIndex;
+	if(index==endIndex)
+		return;
+
+	TSegment** pS = iSegments+(index>>KPageArraySegmentShift);
+
+	MmuLock::Lock();
+
+	do
+		{
+		// get segment...
+		TSegment* s = *pS++;
+		TPhysAddr* p = s->iPages+(index&KPageArraySegmentMask);
+		TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+		TUint limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+
+		// veto pages in segment...
+		do
+			{
+			TPhysAddr page = *p++;
+			TRACE2(("RPageArray::TIter::Veto() yes/no=%d page=0x%08x",IsPresent(page) && TargetStateIsDecommitted(page),page));
+			if(IsPresent(page) && TargetStateIsDecommitted(page))
+				p[-1] = page|EUnmapVetoed;
+			}
+		while(++index<limit);
+
+		MmuLock::Flash();
+		}
+	while(index<endIndex);
+
+	MmuLock::Unlock();
+	}
+	
+
+void RPageArray::TIter::VetoRestrict(TBool aPageMoving)
+	{
+	TUint index = iIndex;
+	TUint endIndex = iEndIndex;
+	if(index==endIndex)
+		return;
+
+	RPageArray::TState operation = 	aPageMoving ? RPageArray::EMoving : RPageArray::ERestrictingNA;
+
+	TSegment** pS = iSegments+(index>>KPageArraySegmentShift);
+
+	MmuLock::Lock();
+
+	do
+		{
+		// get segment...
+		TSegment* s = *pS++;
+		TPhysAddr* p = s->iPages+(index&KPageArraySegmentMask);
+		TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+		TUint limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+
+		// veto pages in segment...
+		do
+			{
+			TPhysAddr page = *p++;
+			TRACE2(("RPageArray::TIter::VetoRestrict() yes/no=%d page=0x%08x",State(page)==operation,page));
+			if(State(page)==operation)
+				{
+				// to veto a 'restrict page' operation, we put the page back into the committed...
+				p[-1] = (page&~EStateMask)|ECommitted;
+				}
+			}
+		while(++index<limit);
+
+		MmuLock::Flash();
+		}
+	while(index<endIndex);
+
+	MmuLock::Unlock();
+	}
+	
+
+FORCE_INLINE void RPageArray::TIter::Set(RPageArray::TSegment** aSegments, TUint aIndex, TUint aEndIndex)
+	{
+	iSegments = aSegments;
+	iIndex = aIndex;
+	iEndIndex = aEndIndex;
+	}
+
+
+//
+// RPageArray
+//
+
+void RPageArray::Init2A()
+	{
+	TInt r = PageSegmentAllocator.Construct();
+	__NK_ASSERT_ALWAYS(r==KErrNone);
+	}
+
+
+void RPageArray::Init2B(DMutex* aLock)
+	{
+	// construct memory object for slabs...
+	DMemoryObject* memory;
+	TMappingCreateFlags mapFlags = (TMappingCreateFlags)(EMappingCreateFixedVirtual|EMappingCreateReserveAllResources);
+	TMemoryAttributes memAttr = EMemoryAttributeStandard;
+	TInt r = MM::InitFixedKernelMemory(memory, KPageArraySegmentBase, KPageArraySegmentEnd, KPageSize, EMemoryObjectUnpaged, EMemoryCreateNoWipe, memAttr, mapFlags);
+	__NK_ASSERT_ALWAYS(r==KErrNone);
+	MM::MemorySetLock(memory,aLock);
+	PageSegmentAllocator.SetMemory(memory,1);
+	}
+
+
+RPageArray::RPageArray()
+	{
+	__NK_ASSERT_DEBUG(!iSegments);
+	}
+
+
+TInt RPageArray::Construct(TUint aMaxPages, TBool aPreallocateMemory)
+	{
+	iNumSegments = (aMaxPages+KPageArraySegmentMask)>>KPageArraySegmentShift;
+	iSegments = (TSegment**)Kern::AllocZ(iNumSegments*sizeof(TSegment*));
+	if(!iSegments)
+		return KErrNoMemory;
+
+	if(!aPreallocateMemory)
+		return KErrNone;
+
+	return PreallocateMemory();
+	}
+
+
+TInt RPageArray::PreallocateMemory()
+	{
+	MmuLock::Lock();
+
+	__NK_ASSERT_DEBUG(!iPreallocatedMemory);
+	iPreallocatedMemory = true;
+
+	TSegment** pS = iSegments;
+	TSegment** pGEnd = pS+iNumSegments;
+	do
+		{
+		if(!GetOrAllocateSegment(pS,1))
+			{
+			iNumSegments = pS-iSegments; // truncate to amount successfully allocated
+			MmuLock::Unlock();
+			return KErrNoMemory;
+			}
+		}
+	while(++pS<pGEnd);
+
+	MmuLock::Unlock();
+	return KErrNone;
+	}
+
+
+RPageArray::~RPageArray()
+	{
+	TSegment** pS = iSegments;
+	if(pS)
+		{
+		TSegment** pGEnd = pS+iNumSegments;
+		if(!iPreallocatedMemory)
+			{
+			// check all segments have already been deleted...
+			while(pS<pGEnd)
+				{
+#ifdef _DEBUG
+				if(*pS)
+					(*pS)->Dump();
+#endif
+				__NK_ASSERT_DEBUG(!*pS);
+				++pS;
+				}
+			}
+		else
+			{
+			MmuLock::Lock();
+			while(pS<pGEnd)
+				{
+				__NK_ASSERT_DEBUG(*pS);
+				TSegment::Unlock(*pS);
+#ifdef _DEBUG
+				if(*pS)
+					(*pS)->Dump();
+#endif
+				__NK_ASSERT_DEBUG(!*pS);
+				TRACE2(("RPageArray::~RPageArray delete segment=%d",pS-iSegments));
+				++pS;
+				if(pS<pGEnd)
+					MmuLock::Flash();
+				}
+			MmuLock::Unlock();
+			}
+
+		Kern::Free(iSegments);
+		}
+	}
+
+
+RPageArray::TSegment* RPageArray::GetOrAllocateSegment(TSegment** aSegmentEntry, TUint aLockCount)
+	{
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	__NK_ASSERT_DEBUG(aLockCount);
+
+	for(;;)
+		{
+		TSegment* s = *aSegmentEntry;
+		if(s)
+			{
+			s->Lock(aLockCount);
+			return s;
+			}
+
+		// no segment, so allocate one...
+		MmuLock::Unlock();
+		s = TSegment::New();
+		MmuLock::Lock();
+		if(!s)
+			return s;
+
+		// if someone else allocated one...
+		if(*aSegmentEntry)
+			{
+			// free the one we created...
+			TSegment::Unlock(s); 
+			//and retry...
+			continue;
+			}
+
+		// use new segment...
+		TRACE2(("RPageArray::GetOrAllocateSegment new segment=%d",aSegmentEntry-iSegments));
+		*aSegmentEntry = s;
+		if(--aLockCount)
+			s->Lock(aLockCount);
+		return s;
+		}
+	}
+
+
+TInt RPageArray::Alloc(TUint aIndex, TUint aCount)
+	{
+	TRACE2(("RPageArray::Alloc(0x%x,0x%x)",aIndex,aCount));
+	__NK_ASSERT_DEBUG(aIndex+aCount<=iNumSegments*KPageArraySegmentSize);
+	__NK_ASSERT_DEBUG(aIndex+aCount>=aIndex);
+
+	MmuLock::Lock();
+
+	TUint index = aIndex;
+	TUint endIndex = aIndex+aCount;
+	TSegment** pS = iSegments+(index>>KPageArraySegmentShift);
+	while(index<endIndex)
+		{
+		TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+		TUint limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+		TUint lockCount = limit-index;
+		index = limit;
+		TSegment* s = GetOrAllocateSegment(pS++,lockCount);
+		if(!s)
+			goto no_memory;
+		}
+
+	MmuLock::Unlock();
+	return KErrNone;
+
+no_memory:
+	MmuLock::Unlock();
+
+	// free what we actually alloced...
+	endIndex = index&~KPageArraySegmentMask;
+	Free(aIndex,endIndex-aIndex);
+
+	return KErrNoMemory;
+	}
+
+
+void RPageArray::Free(TUint aIndex, TUint aCount)
+	{
+	TRACE2(("RPageArray::Free(0x%x,0x%x)",aIndex,aCount));
+	__NK_ASSERT_DEBUG(aIndex+aCount<=iNumSegments*KPageArraySegmentSize);
+	__NK_ASSERT_DEBUG(aIndex+aCount>aIndex);
+
+	MmuLock::Lock();
+
+	TUint index = aIndex;
+	TUint endIndex = aIndex+aCount;
+	TSegment** pS = iSegments+(index>>KPageArraySegmentShift);
+	while(index<endIndex)
+		{
+		__NK_ASSERT_DEBUG(*pS);
+		TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+		TUint limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+		TSegment::Unlock(*pS,limit-index);
+		index = limit;
+		++pS;
+		}
+
+	MmuLock::Unlock();
+	}
+
+
+TInt RPageArray::AddStart(TUint aIndex, TUint aCount, TIter& aIter, TBool aAllowExisting)
+	{
+	TRACE2(("RPageArray::AddStart(0x%x,0x%x,?,%d)",aIndex,aCount,aAllowExisting));
+	__NK_ASSERT_DEBUG(aIndex+aCount<=iNumSegments*KPageArraySegmentSize);
+	__NK_ASSERT_DEBUG(aIndex+aCount>aIndex);
+
+	aIter.Set(iSegments,aIndex,aIndex+aCount);
+
+	MmuLock::Lock();
+
+	TInt r;
+	TUint index = aIndex;
+	TUint endIndex = aIndex+aCount;
+	TSegment** pS = iSegments+(index>>KPageArraySegmentShift);
+	while(index<endIndex)
+		{
+		TSegment* s = *pS;
+		if(!s)
+			{
+			// no segment, so allocate one...
+			MmuLock::Unlock();
+			s = TSegment::New();
+			MmuLock::Lock();
+			if(!s)
+				goto no_memory;
+
+			// if someone else allocated one
+			if(*pS)
+				{
+				// free the one we created...
+				TSegment::Unlock(s); 
+				//and retry...
+				continue;
+				}
+
+			// use new segment...
+			TRACE2(("RPageArray::AddStart new segment=%d",pS-iSegments));
+			*pS = s;
+
+			// move on...
+			index = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+			}
+		else
+			{
+			TUint nextIndex = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+			if(aAllowExisting)
+				{
+				// just move on to next segment...
+				index = (index+KPageArraySegmentSize)&~KPageArraySegmentMask;
+				}
+			else
+				{
+				// check page entries are empty...
+				TPhysAddr* p = s->iPages+(index&KPageArraySegmentMask);
+				TUint limit = (nextIndex<endIndex) ? nextIndex : endIndex;
+				do
+					{
+					if(IsPresent(*p++))
+						goto already_exists;
+					}
+				while(++index<limit);
+				}
+			// lock segment so that it doesn't go away...
+			s->Lock();
+
+			if(index<endIndex)
+				MmuLock::Flash();
+			}
+		++pS;
+		}
+
+	// done...
+	MmuLock::Unlock();
+	return KErrNone;
+
+no_memory:
+	r = KErrNoMemory;
+	goto error;
+already_exists:
+	r = KErrAlreadyExists;
+error:
+	MmuLock::Unlock();
+
+	// unlock any segments that we locked...
+	endIndex = index&~KPageArraySegmentMask;
+	if(endIndex>aIndex)
+		Release(iSegments,aIndex,endIndex-aIndex);
+
+	// return error...
+	return r;
+	}
+
+
+void RPageArray::AddEnd(TUint aIndex, TUint aCount)
+	{
+	Release(iSegments,aIndex,aCount);
+	}
+
+
+void RPageArray::FindStart(TUint aIndex, TUint aCount, TIter& aIter)
+	{
+	TRACE2(("RPageArray::FindStart(0x%x,0x%x,?)",aIndex,aCount));
+	__NK_ASSERT_DEBUG(aIndex+aCount<=iNumSegments*KPageArraySegmentSize);
+	__NK_ASSERT_DEBUG(aIndex+aCount>aIndex);
+
+	aIter.Set(iSegments,aIndex,aIndex+aCount);
+	}
+
+
+void RPageArray::Release(TSegment** aSegments, TUint aIndex, TUint aCount)
+	{
+	__NK_ASSERT_DEBUG(aIndex+aCount>aIndex);
+
+	MmuLock::Lock();
+
+	TSegment** pS = aSegments+(aIndex>>KPageArraySegmentShift);
+	TSegment** pGLast = aSegments+((aIndex+aCount-1)>>KPageArraySegmentShift);
+	__NK_ASSERT_DEBUG(pS<=pGLast);
+	TUint flash = 0;
+	do
+		{
+		MmuLock::Flash(flash,KMaxPagesInOneGo);
+		if(TSegment::Unlock(*pS)==0)
+			{
+			TRACE2(("RPageArray::Release delete segment=%d",pS-aSegments));
+			}
+		++pS;
+		}
+	while(pS<=pGLast);
+
+	MmuLock::Unlock();
+	}
+
+
+TPhysAddr* RPageArray::AddPageStart(TUint aIndex, TIter& aPageList)
+	{
+	__NK_ASSERT_DEBUG(aIndex<=iNumSegments*KPageArraySegmentSize);
+
+	MmuLock::Lock();
+	TSegment** pS = iSegments+(aIndex>>KPageArraySegmentShift);
+	TSegment* s = GetOrAllocateSegment(pS,1);
+	MmuLock::Unlock();
+
+	if(!s)
+		return 0;
+
+	aPageList.Set(iSegments,aIndex,aIndex+1);
+
+	return s->iPages+(aIndex&KPageArraySegmentMask);
+	}
+
+
+TPhysAddr* RPageArray::RemovePageStart(TUint aIndex, TIter& aPageList)
+	{
+	__NK_ASSERT_DEBUG(aIndex<=iNumSegments*KPageArraySegmentSize);
+
+	MmuLock::Lock();
+
+	TSegment** pS = iSegments+(aIndex>>KPageArraySegmentShift);
+	TSegment* s = *pS;
+	if(!s)
+		{
+		MmuLock::Unlock();
+		return 0;
+		}
+
+	TPhysAddr* p = s->iPages+(aIndex&KPageArraySegmentMask);
+	TPhysAddr page = *p;
+	if(State(page)<EDecommitting)
+		{
+		MmuLock::Unlock();
+		return 0;
+		}
+
+	*p = (page&~EStateMask)|EDecommitting;
+
+	s->Lock();
+
+	MmuLock::Unlock();
+
+	aPageList.Set(iSegments,aIndex,aIndex+1);
+
+	return p;
+	}
+
+
+TPhysAddr RPageArray::RemovePage(TPhysAddr* aPageEntry)
+	{
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	TPhysAddr page = *aPageEntry;
+	__NK_ASSERT_DEBUG(State(page)!=EStealing); // can't be stealing as that only happens with the RamAllocLock held, which we should already hold if freeing demand paged pages
+	if(State(page)==EDecommitting || State(page)==EDecommitted)
+		{
+		// remove a page...
+		if(page&EUnmapVetoed)
+			{
+			*aPageEntry = (page&~(EUnmapVetoed|EStateMask))|EDecommitted; // change to EDecommitted state
+			}
+		else
+			{
+			*aPageEntry = EEmptyEntry;
+			return page&~KPageMask;
+			}
+		// check not removing managed pages without the RamAllocLock...
+		__NK_ASSERT_DEBUG(RamAllocLock::IsHeld()
+			|| SPageInfo::FromPhysAddr(page)->Type()!=SPageInfo::EManaged);
+		}
+	return KPhysAddrInvalid;
+	}
+
+
+TPhysAddr* RPageArray::RestrictPageNAStart(TUint aIndex, TIter& aPageList)
+	{
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	__NK_ASSERT_DEBUG(aIndex<=iNumSegments*KPageArraySegmentSize);
+
+	TSegment** pS = iSegments+(aIndex>>KPageArraySegmentShift);
+	TSegment* s = *pS;
+	if(!s)
+		return 0;
+
+	TPhysAddr* p = s->iPages+(aIndex&KPageArraySegmentMask);
+	TPhysAddr page = *p;
+	if(State(page) < RPageArray::ERestrictingNA)
+		return 0;
+
+	*p = (page&~EStateMask) | RPageArray::ERestrictingNA;
+
+	s->Lock();
+
+	aPageList.Set(iSegments,aIndex,aIndex+1);
+
+	return p;
+	}
+
+
+TPhysAddr* RPageArray::StealPageStart(TUint aIndex, TIter& aPageList)
+	{
+	__NK_ASSERT_DEBUG(RamAllocLock::IsHeld());
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	__NK_ASSERT_DEBUG(aIndex<=iNumSegments*KPageArraySegmentSize);
+
+	TSegment** pS = iSegments+(aIndex>>KPageArraySegmentShift);
+	TSegment* s = *pS;
+	__NK_ASSERT_DEBUG(s); // we only steal pages in the live list and these can not go away yet because we hold the RamAllocLock
+
+	TPhysAddr* p = s->iPages+(aIndex&KPageArraySegmentMask);
+	TPhysAddr page = *p;
+
+	if(State(page)>EStealing)
+		*p = (page&~EStateMask)|EStealing;
+
+	s->Lock();
+
+	aPageList.Set(iSegments,aIndex,aIndex+1);
+
+	return p;
+	}
+
+
+TPhysAddr* RPageArray::MovePageStart(TUint aIndex, TIter& aPageList)
+	{
+	__NK_ASSERT_DEBUG(RamAllocLock::IsHeld());
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	__NK_ASSERT_DEBUG(aIndex <= iNumSegments*KPageArraySegmentSize);
+
+	TSegment** pS = iSegments+(aIndex>>KPageArraySegmentShift);
+	TSegment* s = *pS;
+	// The segment should always exist for a page that is being moved.
+	__NK_ASSERT_DEBUG(s);
+
+	TPhysAddr* p = s->iPages+(aIndex&KPageArraySegmentMask);
+	TPhysAddr page = *p;
+	if(State(page) <= RPageArray::EMoving)
+		return NULL;
+
+	*p = (page & ~EStateMask) | EMoving;
+
+	aPageList.Set(iSegments, aIndex, aIndex+1);
+
+	return p;
+	}
+
+
+void RPageArray::ReleasePage(TUint aIndex, TInt aDelta)
+	{
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	__NK_ASSERT_DEBUG(aIndex<=iNumSegments*KPageArraySegmentSize);
+
+	TSegment** pS = iSegments+(aIndex>>KPageArraySegmentShift);
+	TSegment* s = *pS;
+	__NK_ASSERT_DEBUG(s); // must exist because FindPageStart/AddPageStart locked it
+
+	__NK_ASSERT_DEBUG(aDelta>=-1 && aDelta<=1);
+	if(aDelta)
+		s->AdjustAllocCount(aDelta);
+
+	if(TSegment::Unlock(*pS)==0)
+		{
+		TRACE2(("RPageArray::ReleasePage delete segment=%d",pS-iSegments));
+		}
+	}
+
+
+TPhysAddr RPageArray::Page(TUint aIndex)
+	{
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	__NK_ASSERT_DEBUG(aIndex<=iNumSegments*KPageArraySegmentSize);
+
+	TSegment** pS = iSegments+(aIndex>>KPageArraySegmentShift);
+	TSegment* s = *pS;
+	if(!s)
+		return ENotPresent;
+	return s->iPages[aIndex&KPageArraySegmentMask];
+	}
+
+
+TPhysAddr* RPageArray::PageEntry(TUint aIndex)
+	{
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	__NK_ASSERT_DEBUG(aIndex<=iNumSegments*KPageArraySegmentSize);
+
+	TSegment** pS = iSegments+(aIndex>>KPageArraySegmentShift);
+	TSegment* s = *pS;
+	if(!s)
+		return NULL;
+	return s->iPages + (aIndex & KPageArraySegmentMask);
+	}
+
+
+TUint RPageArray::PagingManagerData(TUint aIndex)
+	{
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	__NK_ASSERT_DEBUG(aIndex<=iNumSegments*KPageArraySegmentSize);
+	TSegment** pS = iSegments+(aIndex>>KPageArraySegmentShift);
+	TSegment* s = *pS;
+	__NK_ASSERT_DEBUG(s);
+	TPhysAddr* p = &s->iPages[aIndex&KPageArraySegmentMask];
+
+	TPhysAddr entry = *p;
+	if(IsPresent(entry))
+		{
+#ifdef _DEBUG
+		SPageInfo* pi = SPageInfo::SafeFromPhysAddr(entry&~KPageMask);
+		if(!pi)
+			Kern::Printf("RPageArray::PagingManagerData bad entry 0x%08x",entry);
+		__NK_ASSERT_DEBUG(pi);
+#else
+		SPageInfo* pi = SPageInfo::FromPhysAddr(entry);
+#endif
+		entry = pi->PagingManagerData();
+		}
+	__NK_ASSERT_DEBUG((entry&(EFlagsMask|EStateMask))==ENotPresent);
+
+	return entry>>(EFlagsShift+EStateShift);
+	}
+
+
+void RPageArray::SetPagingManagerData(TUint aIndex, TUint aValue)
+	{
+	aValue = (aValue<<(EFlagsShift+EStateShift))|ENotPresent;
+
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	__NK_ASSERT_DEBUG(aIndex<=iNumSegments*KPageArraySegmentSize);
+	TSegment** pS = iSegments+(aIndex>>KPageArraySegmentShift);
+	TSegment* s = *pS;
+	__NK_ASSERT_DEBUG(s);
+	TPhysAddr* p = &s->iPages[aIndex&KPageArraySegmentMask];
+
+	TPhysAddr entry = *p;
+	if(!IsPresent(entry))
+		*p = aValue;
+	else
+		{
+#ifdef _DEBUG
+		SPageInfo* pi = SPageInfo::SafeFromPhysAddr(entry&~KPageMask);
+		if(!pi)
+			Kern::Printf("RPageArray::SetPagingManagerData bad entry 0x%08x",entry);
+		__NK_ASSERT_DEBUG(pi);
+#else
+		SPageInfo* pi = SPageInfo::FromPhysAddr(entry);
+#endif
+		pi->SetPagingManagerData(aValue);
+		}
+	}
+
+
+TPhysAddr RPageArray::PhysAddr(TUint aIndex)
+	{
+	__NK_ASSERT_DEBUG(MmuLock::IsHeld());
+	__NK_ASSERT_DEBUG(aIndex<=iNumSegments*KPageArraySegmentSize);
+
+	TSegment** pS = iSegments+(aIndex>>KPageArraySegmentShift);
+	TSegment* s = *pS;
+	if(s)
+		{
+		TPhysAddr page = s->iPages[aIndex&KPageArraySegmentMask];
+		if(IsPresent(page))
+			{
+			return page&~KPageMask;
+			}
+		}
+	return KPhysAddrInvalid;
+	}
+
+
+TInt RPageArray::PhysAddr(TUint aIndex, TUint aCount, TPhysAddr& aPhysicalAddress, TPhysAddr* aPhysicalPageList)
+	{
+	__NK_ASSERT_DEBUG(aCount);
+	MmuLock::Lock();
+
+	TUint32* pageList = aPhysicalPageList;
+
+	// get first page...
+	TPhysAddr physStart = PhysAddr(aIndex++);
+	if(physStart==KPhysAddrInvalid)
+		{
+		MmuLock::Unlock();
+		return KErrNotFound;
+		}
+	if(pageList)
+		*pageList++ = physStart;
+
+	TUint32 nextPhys = physStart+KPageSize;
+
+	TUint flash = 0;
+	while(--aCount)
+		{
+		MmuLock::Flash(flash,KMaxPagesInOneGo);
+
+		// get next page...
+		TPhysAddr phys = PhysAddr(aIndex++);
+		if(phys==KPhysAddrInvalid)
+			{
+			MmuLock::Unlock();
+			return KErrNotFound;
+			}
+		if(pageList)
+			*pageList++ = phys;
+
+		// check for contiguity...
+		if(phys!=nextPhys)
+			nextPhys = KPhysAddrInvalid;
+		else
+			nextPhys += KPageSize;
+		}
+
+	MmuLock::Unlock();
+
+	if(nextPhys==KPhysAddrInvalid)
+		{
+		// memory is discontiguous...
+		if(!aPhysicalPageList)
+			return KErrNotFound;
+		aPhysicalAddress = KPhysAddrInvalid;
+		return 1;
+		}
+	else
+		{
+		// memory is contiguous...
+		aPhysicalAddress = physStart;
+		return KErrNone;
+		}
+	}
+
+