Virtual memory abstract interface. More...

#include <MemoryContext.h>

Inheritance diagram for MemoryContext:

Public Types
enum	Result { Success, InvalidAddress, InvalidSize, AlreadyExists, OutOfMemory }
	Result codes. More...

typedef enum MemoryContext::Result	Result
	Result codes. More...

Public Member Functions
	MemoryContext (MemoryMap map, SplitAllocator alloc)
	Constructor. More...

virtual	~MemoryContext ()
	Destructor. More...

virtual Result	initialize ()=0
	Initialize the MemoryContext. More...

virtual Result	activate (bool initializeMMU=false)=0
	Activate the MemoryContext. More...

virtual Result	map (Address virt, Address phys, Memory::Access access)=0
	Map a physical page to a virtual address. More...

virtual Result	unmap (Address virt)=0
	Unmap a virtual address. More...

virtual Result	lookup (Address virt, Address *phys) const =0
	Translate virtual address to physical address. More...

virtual Result	access (Address virt, Memory::Access *access) const =0
	Get Access flags for a virtual address. More...

virtual Result	mapRangeContiguous (Memory::Range *range)
	Map a range of contiguous physical pages to virtual addresses. More...

virtual Result	mapRangeSparse (Memory::Range *range)
	Map and allocate a range of sparse (non-contiguous) physical pages to virtual addresses. More...

virtual Result	unmapRange (Memory::Range *range)
	Unmaps a range of virtual memory. More...

virtual Result	release (Address virt)
	Release a memory page mapping. More...

virtual Result	releaseRange (Memory::Range *range)=0
	Release a range of physical memory by its virtual memory pages. More...

virtual Result	releaseSection (const Memory::Range &range, const bool tablesOnly=false)=0
	Release memory sections. More...

virtual Result	findFree (Size size, MemoryMap::Region region, Address *virt) const
	Find unused memory. More...

virtual void	mapRangeSparseCallback (Address *phys)
	Callback to provide intermediate Range object during mapRangeSparse() More...

Static Public Member Functions
static MemoryContext *	getCurrent ()
	Get currently active MemoryContext. More...

Protected Attributes
SplitAllocator *	m_alloc
	Physical memory allocator. More...

MemoryMap *	m_map
	Virtual memory layout. More...

Callback< MemoryContext, Address >	m_mapRangeSparseCallback
	Callback object for mapRangeSparseCallback function. More...

Memory::Range *	m_savedRange
	Saved range input for use in the mapRangeSparse Callback. More...

Size	m_numSparsePages
	Number of pages allocated via mapRangeSparse Callback. More...

Static Protected Attributes
static MemoryContext *	m_current = 0
	The currently active MemoryContext. More...

Detailed Description

Virtual memory abstract interface.

Definition at line 42 of file MemoryContext.h.

Member Typedef Documentation

◆ Result

typedef enum MemoryContext::Result MemoryContext::Result

Result codes.

Member Enumeration Documentation

◆ Result

enum MemoryContext::Result

Result codes.

Enumerator
Success
InvalidAddress
InvalidSize
AlreadyExists
OutOfMemory

Definition at line 49 of file MemoryContext.h.

Constructor & Destructor Documentation

◆ MemoryContext()

MemoryContext::MemoryContext	(	MemoryMap *	map,
		SplitAllocator *	alloc
	)

Constructor.

Parameters

map	Pointer to memory map to use.
alloc	Allocator used to allocate page tables.

Definition at line 28 of file MemoryContext.cpp.

◆ ~MemoryContext()

MemoryContext::~MemoryContext ( )

virtual

Destructor.

Definition at line 37 of file MemoryContext.cpp.

Member Function Documentation

◆ access()

virtual Result MemoryContext::access	(	Address	virt,
		Memory::Access *	access
	)		const

pure virtual

Get Access flags for a virtual address.

Parameters

virt	Virtual address to get Access flags for.
access	MemoryAccess object pointer.

Returns: Result code.

Implemented in IntelPaging, and ARMPaging.

Referenced by ProcessShares::createShare(), and VMCtlHandler().

◆ activate()

virtual Result MemoryContext::activate ( bool initializeMMU = false )

pure virtual

Activate the MemoryContext.

This function applies this MemoryContext on the hardware MMU.

Parameters

initializeMMU If true perform (re)initialization of the MMU

Returns: Result code.

Implemented in IntelPaging, and ARMPaging.

Referenced by IntelProcess::execute(), and ARMProcess::execute().

◆ findFree()

MemoryContext::Result MemoryContext::findFree	(	Size	size,
		MemoryMap::Region	region,
		Address *	virt
	)		const

virtual

Find unused memory.

This function finds a contigeous block of a given size of virtual memory which is unused and then returns the virtual address of the first page in the block.

Parameters

region	Memory region to search in.
size	Number of bytes requested to be free.
virt	Virtual memory address on output.

Returns: Result code

Definition at line 117 of file MemoryContext.cpp.

References InvalidAddress, lookup(), m_map, OutOfMemory, PAGESIZE, MemoryMap::range(), Memory::Range::size, Success, and Memory::Range::virt.

Referenced by ProcessShares::createShare(), Process::initialize(), IO::map(), VMCopyHandler(), and VMCtlHandler().

◆ getCurrent()

MemoryContext * MemoryContext::getCurrent ( )

static

Get currently active MemoryContext.

Returns: MemoryContext object pointer or NULL.

Definition at line 41 of file MemoryContext.cpp.

References m_current.

Referenced by IO::map(), and IO::unmap().

◆ initialize()

virtual Result MemoryContext::initialize ( )

pure virtual

Initialize the MemoryContext.

Returns: Result code

Implemented in IntelPaging, and ARMPaging.

Referenced by IntelProcess::initialize(), and ARMProcess::initialize().

◆ lookup()

virtual Result MemoryContext::lookup	(	Address	virt,
		Address *	phys
	)		const

pure virtual

Translate virtual address to physical address.

Parameters

virt	Virtual address to lookup
phys	On output contains the translated physical address

Returns: Result code

Implemented in IntelPaging, and ARMPaging.

Referenced by ProcessShares::createShare(), findFree(), release(), VMCopyHandler(), and VMCtlHandler().

◆ map()

virtual Result MemoryContext::map	(	Address	virt,
		Address	phys,
		Memory::Access	access
	)

pure virtual

Map a physical page to a virtual address.

Parameters

virt	Virtual address.
phys	Physical address.
access	Page entry protection flags.

Returns: Result code.

Implemented in IntelPaging, and ARMPaging.

Referenced by Process::initialize(), IO::map(), mapRangeContiguous(), mapRangeSparseCallback(), and VMCopyHandler().

◆ mapRangeContiguous()

MemoryContext::Result MemoryContext::mapRangeContiguous ( Memory::Range * range )

virtual

Map a range of contiguous physical pages to virtual addresses.

Parameters

range Range object describing the range of physical pages.

Returns: Result code.

Definition at line 46 of file MemoryContext.cpp.

References Memory::Range::access, Allocator::Range::address, Allocator::Range::alignment, SplitAllocator::allocate(), m_alloc, map(), OutOfMemory, PAGESIZE, Memory::Range::phys, Memory::Range::size, Allocator::Range::size, Success, Allocator::Success, and Memory::Range::virt.

Referenced by ProcessShares::createShare(), IntelProcess::initialize(), ARMProcess::initialize(), Process::initialize(), Kernel::loadBootProgram(), and VMCtlHandler().

◆ mapRangeSparse()

MemoryContext::Result MemoryContext::mapRangeSparse ( Memory::Range * range )

virtual

Map and allocate a range of sparse (non-contiguous) physical pages to virtual addresses.

Parameters

range Range object describing the range of physical pages.

Returns: Result code.

Definition at line 76 of file MemoryContext.cpp.

References Allocator::Range::address, Allocator::Range::alignment, SplitAllocator::allocateSparse(), m_alloc, m_mapRangeSparseCallback, m_numSparsePages, m_savedRange, OutOfMemory, Memory::Range::size, Allocator::Range::size, Success, and Allocator::Success.

Referenced by VMCtlHandler().

◆ mapRangeSparseCallback()

void MemoryContext::mapRangeSparseCallback ( Address * phys )

virtual

Callback to provide intermediate Range object during mapRangeSparse()

Parameters

phys	Pointer to physical address value of newly allocated page.

See also: mapRangeSparse

Definition at line 146 of file MemoryContext.cpp.

References Memory::Range::access, assert, m_numSparsePages, m_savedRange, map(), PAGESIZE, Success, and Memory::Range::virt.

◆ release()

MemoryContext::Result MemoryContext::release ( Address virt )

virtual

Release a memory page mapping.

Parameters

virt	Virtual address of the page to release.

Returns: Result code

Definition at line 106 of file MemoryContext.cpp.

References lookup(), m_alloc, SplitAllocator::release(), and Success.

◆ releaseRange()

virtual Result MemoryContext::releaseRange ( Memory::Range * range )

pure virtual

Release a range of physical memory by its virtual memory pages.

Parameters

range Range object describing the range of physical pages to release.

Returns: Result code

Implemented in IntelPaging, and ARMPaging.

Referenced by VMCtlHandler().

◆ releaseSection()

virtual Result MemoryContext::releaseSection	(	const Memory::Range &	range,
		const bool	tablesOnly = `false`
	)

pure virtual

Release memory sections.

Deallocate all associated physical memory which resides in the given memory section range.

Parameters

range	Range of memory sections to release
tablesOnly	True to only release associated page tables and do not release the actual mapped pages

Returns: Result code

Implemented in IntelPaging, and ARMPaging.

Referenced by VMCtlHandler(), and Process::~Process().

◆ unmap()

virtual Result MemoryContext::unmap ( Address virt )

pure virtual

Unmap a virtual address.

This function removes a virtual to physical memory mapping without deallocating any physical memory.

Parameters

virt	Virtual address to unmap.

Returns: Result code

Implemented in IntelPaging, and ARMPaging.

Referenced by Process::initialize(), unmapRange(), and VMCopyHandler().

◆ unmapRange()

MemoryContext::Result MemoryContext::unmapRange ( Memory::Range * range )

virtual

Unmaps a range of virtual memory.

Parameters

range Range object describing the range of virtual addresses.

Returns: Result code

Definition at line 95 of file MemoryContext.cpp.

References PAGESIZE, Memory::Range::size, Success, unmap(), and Memory::Range::virt.

Referenced by ProcessShares::releaseShare(), IO::unmap(), and VMCtlHandler().

Field Documentation

◆ m_alloc

SplitAllocator* MemoryContext::m_alloc

protected

Physical memory allocator.

Definition at line 227 of file MemoryContext.h.

Referenced by ARMPaging::access(), IntelPaging::access(), ARMPaging::initialize(), IntelPaging::initialize(), ARMPaging::lookup(), IntelPaging::lookup(), ARMPaging::map(), IntelPaging::map(), mapRangeContiguous(), mapRangeSparse(), release(), ARMPaging::releaseRange(), IntelPaging::releaseRange(), ARMPaging::releaseSection(), IntelPaging::releaseSection(), ARMPaging::unmap(), IntelPaging::unmap(), ARMPaging::~ARMPaging(), and IntelPaging::~IntelPaging().

◆ m_current

MemoryContext * MemoryContext::m_current = 0

staticprotected

The currently active MemoryContext.

Definition at line 233 of file MemoryContext.h.

Referenced by ARMPaging::activate(), IntelPaging::activate(), getCurrent(), ARMPaging::map(), IntelPaging::map(), ARMPaging::unmap(), and IntelPaging::unmap().

◆ m_map

MemoryMap* MemoryContext::m_map

protected

Virtual memory layout.

Definition at line 230 of file MemoryContext.h.

Referenced by findFree(), ARMPaging::initialize(), and IntelPaging::initialize().

◆ m_mapRangeSparseCallback

Callback<MemoryContext, Address> MemoryContext::m_mapRangeSparseCallback

protected

Callback object for mapRangeSparseCallback function.

Definition at line 236 of file MemoryContext.h.

Referenced by mapRangeSparse().

◆ m_numSparsePages

Size MemoryContext::m_numSparsePages

protected

Number of pages allocated via mapRangeSparse Callback.

Definition at line 242 of file MemoryContext.h.

Referenced by mapRangeSparse(), and mapRangeSparseCallback().

◆ m_savedRange

Memory::Range* MemoryContext::m_savedRange

protected

Saved range input for use in the mapRangeSparse Callback.

Definition at line 239 of file MemoryContext.h.

Referenced by mapRangeSparse(), and mapRangeSparseCallback().

The documentation for this class was generated from the following files:

lib/libarch/MemoryContext.h
lib/libarch/MemoryContext.cpp

Public Types

Public Member Functions

Static Public Member Functions

Protected Attributes

Static Protected Attributes

Detailed Description

Member Typedef Documentation

◆ Result

Member Enumeration Documentation

◆ Result

Constructor & Destructor Documentation

◆ MemoryContext()

◆ ~MemoryContext()

Member Function Documentation

◆ access()

◆ activate()

◆ findFree()

◆ getCurrent()

◆ initialize()

◆ lookup()

◆ map()

◆ mapRangeContiguous()

◆ mapRangeSparse()

◆ mapRangeSparseCallback()

◆ release()

◆ releaseRange()

◆ releaseSection()

◆ unmap()

◆ unmapRange()

Field Documentation

◆ m_alloc

◆ m_current

◆ m_map

◆ m_mapRangeSparseCallback

◆ m_numSparsePages

◆ m_savedRange