// Copyright (c) 2006-2009 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:

 // e32\memmodel\epoc\moving\mdefrag.cpp

 // 

 //

 #include <memmodel.h>

 #include <defrag.h>

 #include "mmboot.h"

 #include <mmubase.inl>

 #include <ramalloc.h>

 #include "cache_maintenance.h"

 /*

  * Move a kernel page from aOld to aNew, updating the page table in aChunk.

  * Enter with system locked, exit with system unlocked (!!)

  * Must hold RAM alloc mutex.

  */

 TInt Mmu::MoveKernelPage(DChunk* aChunk, TUint32 aOffset, TPhysAddr aOld, TPhysAddr& aNew, TUint aBlockZoneId, TBool aBlockRest)

 	{

 	__KTRACE_OPT(KMMU,Kern::Printf("Mmu::MoveKernelPage() off=%08x old=%08x",aOffset,aOld));

 	Mmu& m=Mmu::Get();

 	// Release the system lock - the kernel chunks can't ever be freed

 	// and the ramalloc mutex protects us from decommit.

 	NKern::UnlockSystem();

 	DMemModelChunk* chunk = (DMemModelChunk*)aChunk;

 	// Allocate new page, map it uncached but buffered, and find old mapping

 	TPhysAddr newPage;

 	if (m.AllocRamPages(&newPage, 1, EPageMovable, aBlockZoneId, aBlockRest) != KErrNone)

 		return KErrNoMemory;

 	TLinAddr vOld = (TLinAddr)chunk->iBase + aOffset;

 	TLinAddr vNew = m.MapTemp(newPage, EFalse);

 	// Find page table for mapping

 	TInt ptid=m.GetPageTableId(vOld);

 	if(ptid<0)

 		Panic(EDefragKernelChunkNoPageTable);

 	// With the system lock, ask Mmu to remap the page.

 	// This will copy and remap it with interrupts disabled, while

 	// avoiding touching any cache lines on the heap.

 	NKern::LockSystem();

 	m.RemapKernelPage(ptid, vOld, vNew, newPage, chunk->iPtePermissions);

 	// update new pageinfo, clear old, then done with system lock.

 	SPageInfo* oldpi = SPageInfo::FromPhysAddr(aOld);

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

 	pi->Set(oldpi->Type(),oldpi->Owner(),oldpi->Offset());

 	oldpi->SetUnused();

 	NKern::UnlockSystem();

 	// Remove temporary new page mapping

 	m.UnmapTemp();

 	// Remove old page from external cache - RemapKernelPage has already removed it from internal cache.

 	CacheMaintenance::PageToReusePhysicalCache(aOld);

 	// Free old page

 #ifdef _DEBUG

 	m.ClearPages(1, (TPhysAddr*)(aOld|1));

 #endif

 	m.iRamPageAllocator->FreeRamPage(aOld, EPageMovable);

 	aNew = newPage;

 	return KErrNone;

 	}

 /* 

  * These pages don't exist on moving memory model, no need to move them

  * but this function must exist to make the kernel link.

  */

 TInt Mmu::MoveCodeSegMemoryPage(DMemModelCodeSegMemory* /*aCodeSegMemory*/, TUint32 /*aOffset*/, TPhysAddr /*aOld*/,

 		TPhysAddr& /*aNew*/, TUint /*aBlockZoneId*/, TBool /*aBlockRest*/)

 	{

 	NKern::UnlockSystem();

 	return KErrNotSupported;

 	}

 /*

  * Move a code chunk page from aOld to aNew, updating the page table in aChunk.

  * Enter with system locked, exit with system unlocked (!!)

  * Must hold RAM alloc mutex.

  */

 TInt Mmu::MoveCodeChunkPage(DChunk* aChunk, TUint32 aOffset, TPhysAddr aOld, TPhysAddr& aNew, TUint aBlockZoneId, TBool aBlockRest)

 	{

 	__KTRACE_OPT(KMMU,Kern::Printf("Mmu::MoveCodeChunkPage() off=%08x old=%08x",aOffset,aOld));

 	Mmu& m=Mmu::Get();

 	// look up the code seg that corresponds to this page

 	TLinAddr aLinearAddress = (TLinAddr)(aChunk->Base() + aOffset);

 	DMemModelCodeSeg* codeseg = (DMemModelCodeSeg*)DCodeSeg::CodeSegsByAddress.Find(aLinearAddress);

 	// if the code seg is not done loading yet, we can't move it the easy way

 	// also, if it's being unloaded the codeseg will have gone.

 	if (!codeseg || !(codeseg->iMark & DCodeSeg::EMarkLoaded))

 		{

 		NKern::UnlockSystem();

 		return KErrInUse;

 		}

 	// Release system lock as page can't be decommitted while we hold ramalloc mutex

 	NKern::UnlockSystem();

 	// Allocate new page, map it uncached but buffered, and find old mapping

 	TPhysAddr newPage;

 	if (m.AllocRamPages(&newPage, 1, EPageMovable, aBlockZoneId, aBlockRest) != KErrNone)

 		return KErrNoMemory;

 	TLinAddr vOld = aLinearAddress;

 	TLinAddr vNew = m.MapTemp(newPage, EFalse);

 	// Copy the page and remap it

 	pagecpy((TAny*)vNew, (TAny*)vOld);

 	NKern::LockSystem();

 	// Substitute drains the write buffer for us during the remap.

 	aChunk->Substitute(aOffset, aOld, newPage);

 	NKern::UnlockSystem();

 	// Remove temporary new page mapping

 	m.UnmapTemp();

 	// Remove old page from physical cache

 	CacheMaintenance::PageToReusePhysicalCache(aOld);

 	// Free old page

 #ifdef _DEBUG

 	m.ClearPages(1, (TPhysAddr*)(aOld|1));

 #endif

 	m.iRamPageAllocator->FreeRamPage(aOld, EPageMovable);

 	aNew = newPage;

 	return KErrNone;

 	}

 /*

  * Move a data chunk page from aOld to aNew, updating the page table in aChunk.

  * Enter with system locked, exit with system unlocked (!!)

  * Must hold RAM alloc mutex.

  */

 TInt Mmu::MoveDataChunkPage(DChunk* aChunk, TUint32 aOffset, TPhysAddr aOld, TPhysAddr& aNew, TUint aBlockZoneId, TBool aBlockRest)

 	{

 	__KTRACE_OPT(KMMU,Kern::Printf("Mmu::MoveDataChunkPage() off=%08x old=%08x",aOffset,aOld));

 	Mmu& m=Mmu::Get();

 	TInt r;

 	// Release system lock as page can't be decommitted while we hold ramalloc mutex

 	NKern::UnlockSystem();

 	// Allocate new page, map it uncached but buffered

 	TPhysAddr newPage;

 	if (m.AllocRamPages(&newPage, 1, EPageMovable, aBlockZoneId, aBlockRest) != KErrNone)

 		return KErrNoMemory;

 	TLinAddr vNew = m.MapTemp(newPage, EFalse);

 	// Mark the PTE as inaccessible to avoid the data being overwritten while we copy

 	// This also takes care of the cache requirements to alias the page elsewhere,

 	// since it can't be copied from an inaccessible PTE

 	DisablePageModification((DMemModelChunk*)aChunk, aOffset);

 	TLinAddr vOldAlias = m.MapSecondTemp(aOld, ETrue);

 	// Copy the page's contents and remap its PTE

 	pagecpy((TAny*)vNew, (TAny*)vOldAlias);

 	NKern::LockSystem();

 	if (iDisabledPte != NULL)

 		{

 		// Access wasn't reenabled, so we can continue

 		aChunk->Substitute(aOffset, aOld, newPage);

 		iDisabledAddr = 0;

 		iDisabledPte = NULL;

 		iDisabledOldVal = 0;

 		r = KErrNone;

 		}

 	else

 		r = KErrInUse;

 	NKern::UnlockSystem();

 	// Remove temporary page mappings

 	CacheMaintenance::PageToReuseVirtualCache(vOldAlias);

 	m.UnmapTemp();

 	m.UnmapSecondTemp();

 	if (r == KErrNone)

 		{

 		// Remove old page from physical cache - DisablePageModification removed it from L1 already

 		CacheMaintenance::PageToReusePhysicalCache(aOld);

 		}

 	if (r == KErrNone)

 		{

 		// Free old page

 #ifdef _DEBUG

 		m.ClearPages(1, (TPhysAddr*)(aOld|1));

 #endif

 		m.iRamPageAllocator->FreeRamPage(aOld, EPageMovable);

 		aNew = newPage;

 		}

 	else

 		{

 		// Free new page

 		m.iRamPageAllocator->FreeRamPage(newPage, EPageMovable);

 		}

 	return r;

 	}