// 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 "memmodel.h"

 #include "mm.h"

 #include "mmu.h"

 #include "mpdalloc.h"

 #include "mobject.h"

 #include "cache_maintenance.inl"

 // check enough space for page directories...

 __ASSERT_COMPILE(KNumOsAsids <= (KPageDirectoryEnd-KPageDirectoryBase)/KPageDirectorySize);

 PageDirectoryAllocator PageDirectories;

 const TUint KLocalPdShift = KPageDirectoryShift > KPageShift ? KPageDirectoryShift-1 : KPageShift;

 const TUint KLocalPdSize = 1<<KLocalPdShift;

 const TUint KLocalPdPages = 1<<(KLocalPdShift-KPageShift);

 __ASSERT_COMPILE((KPageDirectoryBase&(31*KPageDirectorySize))==0); // following code assumes this alignment

 void PageDirectoryAllocator::GlobalPdeChanged(TPde* aPde)

 	{

 	__NK_ASSERT_DEBUG(MmuLock::IsHeld());

 	__NK_ASSERT_DEBUG(TLinAddr(aPde)>=KPageDirectoryBase);

 	__NK_ASSERT_DEBUG(TLinAddr(aPde)<KPageDirectoryEnd);

 	__NK_ASSERT_DEBUG(KLocalPdSize==(TUint)KPageDirectorySize); // shouldn't be called if we have separate global PDs

 	TLinAddr addr = (TLinAddr(aPde)&KPageDirectoryMask)*(KChunkSize/sizeof(TPde));

 	if(addr<KGlobalMemoryBase)

 		return; // change was in local part of PD, so nothing to do

 	if(addr-KIPCAlias<KIPCAliasAreaSize)

 		return; // change was in IPC alias area, so nothing to do

 	if(!iAllocator)

 		return; // not yet initialised

 	TRACE2(("PageDirectoryAllocator::GlobalPdeChanged(0x%08x)",aPde));

 	TPde pde = *aPde;

 	TLinAddr pPde = KPageDirectoryBase+(TLinAddr(aPde)&KPageDirectoryMask); // first page directory

 	// copy PDE to all allocated page directories

 	pPde -= KPageDirectorySize; // start off at PD minus one

 	TLinAddr lastPd = KPageDirectoryBase+(KNumOsAsids-1)*KPageDirectorySize;

 	TUint32* ptr = iAllocator->iMap;

 	do

 		{

 		TUint32 bits = ~*ptr++;

 		do

 			{

 			pPde += KPageDirectorySize; // step to next page directory

 			if(bits&0x80000000u)

 				{

 				TRACE2(("!PDE %x=%x",pPde,pde));

 				*(TPde*)pPde = pde;

 				CacheMaintenance::SinglePdeUpdated(pPde);

 				}

 			}

 		while(bits<<=1);

 		pPde |= 31*KPageDirectorySize; // step to next group of 32 PDs

 		}

 	while(pPde<lastPd);

 	}

 void PageDirectoryAllocator::Init2()

 	{

 	TRACEB(("PageDirectoryAllocator::Init2()"));

 	// construct memory object for page directories...

 #if defined(__CPU_PAGE_TABLES_FULLY_CACHED)

 	TMemoryAttributes memAttr = EMemoryAttributeStandard;

 #else

 	TMemoryAttributes memAttr = (TMemoryAttributes)(EMemoryAttributeNormalUncached|EMemoryAttributeDefaultShareable);

 #endif

 	TInt r = MM::InitFixedKernelMemory(iPageDirectoryMemory, KPageDirectoryBase, KPageDirectoryEnd, KPageDirectorySize, EMemoryObjectHardware, EMemoryCreateNoWipe, memAttr, EMappingCreateFixedVirtual);

 	__NK_ASSERT_ALWAYS(r==KErrNone);

 	// initialise kernel page directory...

 	TPhysAddr kernelPd = Mmu::LinearToPhysical((TLinAddr)Mmu::PageDirectory(KKernelOsAsid));

 	iKernelPageDirectory = kernelPd;

 	((DMemModelProcess*)K::TheKernelProcess)->iPageDir = kernelPd;

 	AssignPages(KKernelOsAsid*(KPageDirectorySize>>KPageShift),KPageDirectorySize>>KPageShift,kernelPd);

 	// construct allocator...

 	iAllocator = TBitMapAllocator::New(KNumOsAsids,ETrue);

 	__NK_ASSERT_ALWAYS(iAllocator);

 	iAllocator->Alloc(KKernelOsAsid,1); // kernel page directory already allocated

 	TRACEB(("PageDirectoryAllocator::Init2 done"));

 	}

 void PageDirectoryAllocator::AssignPages(TUint aIndex, TUint aCount, TPhysAddr aPhysAddr)

 	{

 	__NK_ASSERT_DEBUG(aCount<=KMaxPageInfoUpdatesInOneGo);

 	MmuLock::Lock();

 	SPageInfo* pi = SPageInfo::FromPhysAddr(aPhysAddr);

 	SPageInfo* piEnd = pi+aCount;

 	while(pi<piEnd)

 		{

 		pi->SetPhysAlloc(iPageDirectoryMemory,aIndex);

 		++pi;

 		++aIndex;

 		}

 	MmuLock::Unlock();

 	}

 TInt PageDirectoryAllocator::Alloc(TUint aOsAsid, TPhysAddr& aPageDirectory)

 	{

 	TRACE(("PageDirectoryAllocator::Alloc(%d)",aOsAsid));

 	// get memory for local page directory...

 	Mmu& m = TheMmu;

 	TUint offset = aOsAsid*KPageDirectorySize;

 	TPhysAddr pdPhys;

 	RamAllocLock::Lock();

 	TInt r = m.AllocContiguousRam(pdPhys, KLocalPdPages, KLocalPdShift-KPageShift, iPageDirectoryMemory->RamAllocFlags());

 	if(r==KErrNone)

 		AssignPages(offset>>KPageShift,KLocalPdPages,pdPhys);

 	RamAllocLock::Unlock();

 	if(r==KErrNone)

 		{

 		TRACE(("PageDirectoryAllocator::Alloc pdPhys = 0x%08x",pdPhys));

 		// map local page directory...

 		r = MM::MemoryAddContiguous(iPageDirectoryMemory,MM::BytesToPages(offset),KLocalPdPages,pdPhys);

 		if(r!=KErrNone)

 			{

 			RamAllocLock::Lock();

 			m.FreeContiguousRam(pdPhys,KLocalPdPages);

 			RamAllocLock::Unlock();

 			}

 		else

 			{

 			aPageDirectory = pdPhys;

 			TPde* pd = Mmu::PageDirectory(aOsAsid);

 			const TUint globalOffset = (KGlobalMemoryBase>>KChunkShift)*sizeof(TPde); // start of global part

 			// clear local entries in page directory...

 			memclr(pd,globalOffset);

 			CacheMaintenance::PdesInitialised((TLinAddr)pd,globalOffset);

 			if(KLocalPdSize<(TUint)KPageDirectorySize)

 				{

 				// map global page directory after local part...

 				__NK_ASSERT_DEBUG(KLocalPdSize==globalOffset);

 				r = MM::MemoryAddContiguous(iPageDirectoryMemory, MM::BytesToPages(offset+KLocalPdSize), 

 						(KPageDirectorySize-KLocalPdSize)/KPageSize, iKernelPageDirectory+KLocalPdSize);

 				__NK_ASSERT_DEBUG(r==KErrNone); // can't fail

 				MmuLock::Lock(); // need lock because allocator not otherwise atomic

 				iAllocator->Alloc(aOsAsid,1);

 				MmuLock::Unlock();

 				}

 			else

 				{

 				// copy global entries to local page directory...

 				TPde* globalPd = Mmu::PageDirectory(KKernelOsAsid);

 				MmuLock::Lock(); // need lock because allocator not otherwise atomic, also  to make sure GlobalPdeChanged() only accesses extant PDs

 				memcpy((TUint8*)pd+globalOffset,(TUint8*)globalPd+globalOffset,KPageDirectorySize-globalOffset);

 				iAllocator->Alloc(aOsAsid,1);

 				MmuLock::Unlock();

 				CacheMaintenance::PdesInitialised((TLinAddr)((TUint8*)pd+globalOffset),KPageDirectorySize-globalOffset);

 				}

 			}

 		}

 	TRACE(("PageDirectoryAllocator::Alloc returns %d",r));

 	return r;

 	}

 void PageDirectoryAllocator::Free(TUint aOsAsid)

 	{

 	TRACE(("PageDirectoryAllocator::Free(%d)",aOsAsid));

 	MmuLock::Lock(); // need lock because allocator not otherwise atomic, also to make sure GlobalPdeChanged() only accesses extant PDs

 	iAllocator->Free(aOsAsid, 1);

 	MmuLock::Unlock();

 	const TUint KPageDirectoryPageCount = KPageDirectorySize>>KPageShift;

 	TPhysAddr pages[KPageDirectoryPageCount];

 	TUint n = MM::MemoryRemovePages(iPageDirectoryMemory,aOsAsid*KPageDirectoryPageCount,KPageDirectoryPageCount,pages);

 	(void)n;

 	__NK_ASSERT_DEBUG(n==KPageDirectoryPageCount);

 	RamAllocLock::Lock();

 	Mmu& m = TheMmu;

 	// Page directories are fixed.

 	m.FreeRam(pages, KLocalPdPages, EPageFixed);

 	RamAllocLock::Unlock();

 	}