Specialization for accessing a copy-on-write disk image layer. More...

#include <disk_image.hh>

Inheritance diagram for CowDiskImage:

Classes
struct	Sector

Public Types
typedef CowDiskImageParams	Params

Public Types inherited from DiskImage
typedef DiskImageParams	Params

Public Types inherited from SimObject
typedef SimObjectParams	Params

Public Member Functions
	CowDiskImage (const Params *p)

	~CowDiskImage ()

void	notifyFork () override
	Notify a child process of a fork. More...

void	initSectorTable (int hash_size)

bool	open (const std::string &file)

void	save () const

void	save (const std::string &file) const

void	writeback ()

void	serialize (CheckpointOut &cp) const override
	Serialize an object. More...

void	unserialize (CheckpointIn &cp) override
	Unserialize an object. More...

std::streampos	size () const override

std::streampos	read (uint8_t *data, std::streampos offset) const override

std::streampos	write (const uint8_t *data, std::streampos offset) override

Public Member Functions inherited from DiskImage
	DiskImage (const Params *p)

virtual	~DiskImage ()

Public Member Functions inherited from SimObject
const Params *	params () const

	SimObject (const Params *_params)

virtual	~SimObject ()

virtual const std::string	name () const

virtual void	init ()
	init() is called after all C++ SimObjects have been created and all ports are connected. More...

virtual void	loadState (CheckpointIn &cp)
	loadState() is called on each SimObject when restoring from a checkpoint. More...

virtual void	initState ()
	initState() is called on each SimObject when not restoring from a checkpoint. More...

virtual void	regProbePoints ()
	Register probe points for this object. More...

virtual void	regProbeListeners ()
	Register probe listeners for this object. More...

ProbeManager *	getProbeManager ()
	Get the probe manager for this object. More...

virtual Port &	getPort (const std::string &if_name, PortID idx=InvalidPortID)
	Get a port with a given name and index. More...

virtual void	startup ()
	startup() is the final initialization call before simulation. More...

DrainState	drain () override
	Provide a default implementation of the drain interface for objects that don't need draining. More...

virtual void	memWriteback ()
	Write back dirty buffers to memory using functional writes. More...

virtual void	memInvalidate ()
	Invalidate the contents of memory buffers. More...

void	serialize (CheckpointOut &cp) const override
	Serialize an object. More...

void	unserialize (CheckpointIn &cp) override
	Unserialize an object. More...

Public Member Functions inherited from EventManager
EventQueue *	eventQueue () const

void	schedule (Event &event, Tick when)

void	deschedule (Event &event)

void	reschedule (Event &event, Tick when, bool always=false)

void	schedule (Event *event, Tick when)

void	deschedule (Event *event)

void	reschedule (Event *event, Tick when, bool always=false)

void	wakeupEventQueue (Tick when=(Tick) -1)
	This function is not needed by the usual gem5 event loop but may be necessary in derived EventQueues which host gem5 on other schedulers. More...

void	setCurTick (Tick newVal)

	EventManager (EventManager &em)
	Event manger manages events in the event queue. More...

	EventManager (EventManager *em)

	EventManager (EventQueue *eq)

Public Member Functions inherited from Serializable
	Serializable ()

virtual	~Serializable ()

void	serializeSection (CheckpointOut &cp, const char *name) const
	Serialize an object into a new section. More...

void	serializeSection (CheckpointOut &cp, const std::string &name) const

void	unserializeSection (CheckpointIn &cp, const char *name)
	Unserialize an a child object. More...

void	unserializeSection (CheckpointIn &cp, const std::string &name)

Public Member Functions inherited from Drainable
DrainState	drainState () const
	Return the current drain state of an object. More...

Public Member Functions inherited from Stats::Group
	Group (Group parent, const char name=nullptr)
	Construct a new statistics group. More...

virtual	~Group ()

virtual void	regStats ()
	Callback to set stat parameters. More...

virtual void	resetStats ()
	Callback to reset stats. More...

virtual void	preDumpStats ()
	Callback before stats are dumped. More...

void	addStat (Stats::Info *info)
	Register a stat with this group. More...

const std::map< std::string, Group * > &	getStatGroups () const
	Get all child groups associated with this object. More...

const std::vector< Info * > &	getStats () const
	Get all stats associated with this object. More...

void	addStatGroup (const char name, Group block)
	Add a stat block as a child of this block. More...

const Info *	resolveStat (std::string name) const
	Resolve a stat by its name within this group. More...

	Group ()=delete

	Group (const Group &)=delete

Group &	operator= (const Group &)=delete

Static Public Attributes
static const uint32_t	VersionMajor = 1

static const uint32_t	VersionMinor = 0

Protected Types
typedef std::unordered_map< uint64_t, Sector * >	SectorTable

Protected Attributes
std::string	filename

DiskImage *	child

SectorTable *	table

Protected Attributes inherited from DiskImage
bool	initialized

Protected Attributes inherited from SimObject
const SimObjectParams *	_params
	Cached copy of the object parameters. More...

Protected Attributes inherited from EventManager
EventQueue *	eventq
	A pointer to this object's event queue. More...

Additional Inherited Members
Static Public Member Functions inherited from SimObject
static void	serializeAll (CheckpointOut &cp)
	Serialize all SimObjects in the system. More...

static SimObject *	find (const char *name)
	Find the SimObject with the given name and return a pointer to it. More...

Static Public Member Functions inherited from Serializable
static const std::string &	currentSection ()
	Gets the fully-qualified name of the active section. More...

static void	serializeAll (const std::string &cpt_dir)
	Serializes all the SimObjects. More...

static void	unserializeGlobals (CheckpointIn &cp)

Protected Member Functions inherited from Drainable
	Drainable ()

virtual	~Drainable ()

virtual void	drainResume ()
	Resume execution after a successful drain. More...

void	signalDrainDone () const
	Signal that an object is drained. More...

Detailed Description

Specialization for accessing a copy-on-write disk image layer.

A copy-on-write(COW) layer must be stacked on top of another disk image layer this layer can be another CowDiskImage, or a RawDiskImage.

This object is designed to provide a mechanism for persistant changes to a main disk image, or to provide a place for temporary changes to the image to take place that later may be thrown away.

Definition at line 104 of file disk_image.hh.

Member Typedef Documentation

◆ Params

typedef CowDiskImageParams CowDiskImage::Params

Definition at line 122 of file disk_image.hh.

◆ SectorTable

typedef std::unordered_map<uint64_t, Sector *> CowDiskImage::SectorTable

protected

Definition at line 114 of file disk_image.hh.

Constructor & Destructor Documentation

◆ CowDiskImage()

CowDiskImage::CowDiskImage ( const Params * p )

Definition at line 171 of file disk_image.cc.

References fatal, filename, initSectorTable(), open(), MipsISA::p, registerExitCallback(), and save().

◆ ~CowDiskImage()

CowDiskImage::~CowDiskImage ( )

Definition at line 188 of file disk_image.cc.

References ArmISA::i, and table.

Member Function Documentation

◆ initSectorTable()

void CowDiskImage::initSectorTable ( int hash_size )

Definition at line 285 of file disk_image.cc.

References DiskImage::initialized, and table.

Referenced by CowDiskImage().

◆ notifyFork()

void CowDiskImage::notifyFork ( )

overridevirtual

Notify a child process of a fork.

SimObjects are told that the process is going to be forked.

Forking is a process of splitting a process in to two processes, which is then used for multiprocessing.

When calling fork in gem5, we need to ensure that resources shared between the parent and the child are consistent. This method is intended to be overloaded to handle that. For example, an object could use this method to re-open input files to get a separate file description with a private file offset.

This method is only called in the child of the fork. The call takes place in a drained system.

Reimplemented from Drainable.

Definition at line 200 of file disk_image.cc.

References filename, inform, and SimObject::params().

◆ open()

bool CowDiskImage::open ( const std::string & file )

Definition at line 239 of file disk_image.cc.

References ArmISA::i, DiskImage::initialized, ArmISA::offset, panic, SafeRead(), SafeReadSwap(), table, VersionMajor, and VersionMinor.

Referenced by CowDiskImage(), and unserialize().

◆ read()

std::streampos CowDiskImage::read	(	uint8_t *	data,
		std::streampos	offset
	)		const

overridevirtual

Implements DiskImage.

Definition at line 381 of file disk_image.cc.

References child, data, DDUMP, DPRINTF, ArmISA::i, DiskImage::initialized, ArmISA::offset, panic, DiskImage::read(), SectorSize, size(), and table.

◆ save() [1/2]

void CowDiskImage::save ( ) const

Definition at line 321 of file disk_image.cc.

References filename.

Referenced by CowDiskImage(), and serialize().

◆ save() [2/2]

void CowDiskImage::save ( const std::string & file ) const

◆ serialize()

void CowDiskImage::serialize ( CheckpointOut & cp ) const

overridevirtual

Serialize an object.

Output an object's state into the current checkpoint section.

Parameters

cp	Checkpoint state

Implements Serializable.

Definition at line 425 of file disk_image.cc.

References CheckpointIn::dir(), SimObject::name(), save(), and SERIALIZE_SCALAR.

◆ size()

std::streampos CowDiskImage::size ( ) const

overridevirtual

Implements DiskImage.

Definition at line 377 of file disk_image.cc.

References child, and DiskImage::size().

Referenced by read(), and write().

◆ unserialize()

void CowDiskImage::unserialize ( CheckpointIn & cp )

overridevirtual

Unserialize an object.

Read an object's state from the current checkpoint section.

Parameters

cp	Checkpoint state

Implements Serializable.

Definition at line 433 of file disk_image.cc.

References open(), and UNSERIALIZE_SCALAR.

◆ write()

std::streampos CowDiskImage::write	(	const uint8_t *	data,
		std::streampos	offset
	)

overridevirtual

Implements DiskImage.

Definition at line 401 of file disk_image.cc.

References data, DDUMP, DPRINTF, ArmISA::i, DiskImage::initialized, ArmISA::offset, panic, SectorSize, size(), and table.

◆ writeback()

void CowDiskImage::writeback ( )

Definition at line 365 of file disk_image.cc.

References child, ArmISA::i, table, and DiskImage::write().

Member Data Documentation

◆ child

DiskImage* CowDiskImage::child

protected

Definition at line 118 of file disk_image.hh.

Referenced by read(), size(), and writeback().

◆ filename

std::string CowDiskImage::filename

protected

Definition at line 117 of file disk_image.hh.

Referenced by CowDiskImage(), notifyFork(), and save().

◆ table

SectorTable* CowDiskImage::table

protected

Definition at line 119 of file disk_image.hh.

Referenced by initSectorTable(), open(), read(), write(), writeback(), and ~CowDiskImage().

◆ VersionMajor

const uint32_t CowDiskImage::VersionMajor = 1

static

Definition at line 107 of file disk_image.hh.

Referenced by open().

◆ VersionMinor

const uint32_t CowDiskImage::VersionMinor = 0

static

Definition at line 108 of file disk_image.hh.

Referenced by open().

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

dev/storage/disk_image.hh
dev/storage/disk_image.cc

Classes

Public Types

Public Member Functions

Static Public Attributes

Protected Types

Protected Attributes

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ Params

◆ SectorTable

Constructor & Destructor Documentation

◆ CowDiskImage()

◆ ~CowDiskImage()

Member Function Documentation

◆ initSectorTable()

◆ notifyFork()

◆ open()

◆ read()

◆ save() [1/2]

◆ save() [2/2]

◆ serialize()

◆ size()

◆ unserialize()

◆ write()

◆ writeback()

Member Data Documentation

◆ child

◆ filename

◆ table

◆ VersionMajor

◆ VersionMinor