gem5::TranslationGen Class Reference

TranslationGen is a base class for a generator object which returns information about address translations over a range of virtual addresses. More...

#include <translation_gen.hh>

Inheritance diagram for gem5::TranslationGen:

Classes
struct	Range
	This structure represents a single, contiguous translation, or carries information about whatever fault might have happened while attempting it. More...

Public Types
using	const_iterator = TranslationGenConstIterator

Public Member Functions
	TranslationGen (Addr new_start, Addr new_size)
	The starting virtual address and the size of the entire region being translated. More...
virtual	~TranslationGen ()
Addr	start () const
Addr	size () const
const_iterator	begin () const
const_iterator	end () const

Protected Member Functions
virtual void	translate (Range &range) const =0
	Subclasses implement this function to complete TranslationGen. More...

Protected Attributes
Addr	_start
Addr	_size

Friends
class	TranslationGenConstIterator
	A const iterator class is provided so this generator can be used in a range based for loop. More...

Detailed Description

TranslationGen is a base class for a generator object which returns information about address translations over a range of virtual addresses.

An object which can perform translations, like an MMU or one representing an in memory page table, can create one of these when asked to translate a range of virtual addresses. The caller can then retrieve translation information from the generator one bit at a time, until the whole range has been translated and the generator has been exhausted.

This frees the caller from having to know how far ahead a given translation is good for, or in other words where they need to break up the region to translate its individual parts (page boundaries, etc).

This base class manages the bookkeeping during that process. Subclasses are responsible for doing the actual translation, which is requested using the "translate" virtual method.

Definition at line 60 of file translation_gen.hh.

Member Typedef Documentation

const_iterator

using gem5::TranslationGen::const_iterator = TranslationGenConstIterator

Definition at line 122 of file translation_gen.hh.

Constructor & Destructor Documentation

TranslationGen()

gem5::TranslationGen::TranslationGen ( Addr  new_start, Addr  new_size  )

inline

The starting virtual address and the size of the entire region being translated.

Subclass constructors can take whatever additional info they may need, like pointers back to the object actually doing the translation.

Definition at line 106 of file translation_gen.hh.

~TranslationGen()

virtual gem5::TranslationGen::~TranslationGen ( )

inlinevirtual

Definition at line 109 of file translation_gen.hh.

Member Function Documentation

begin()

TranslationGenConstIterator gem5::TranslationGen::begin ( ) const

inline

Definition at line 253 of file translation_gen.hh.

References start().

Referenced by TEST().

end()

TranslationGenConstIterator gem5::TranslationGen::end ( ) const

inline

Definition at line 259 of file translation_gen.hh.

Referenced by TEST().

size()

Addr gem5::TranslationGen::size ( ) const

inline

Definition at line 112 of file translation_gen.hh.

References _size.

Referenced by TEST(), and gem5::TranslationGenConstIterator::update().

start()

Addr gem5::TranslationGen::start ( ) const

inline

Definition at line 111 of file translation_gen.hh.

References _start.

Referenced by begin(), TEST(), and gem5::TranslationGenConstIterator::update().

translate()

virtual void gem5::TranslationGen::translate ( Range &  range ) const

protectedpure virtual

Subclasses implement this function to complete TranslationGen.

It should accept a Range reference which will have its "vaddr" field set to the virtual address to translate, and the "size" field set to the remaining size of the entire region being translated.

If there is a fault performing the translation of "vaddr", then this function should set the "fault" field of range and return.

If the translation was successful, this method should set "paddr" to the corresponding physical address, and set "size" to the number of bytes corresponding to the translation. Or more precisely, size should be set to the maximum "N" where vaddr + n maps to paddr + n for all 0 <= n <= N.

Implemented in TestTranslationGen, gem5::EmulationPageTable::PageTableTranslationGen, gem5::AMDGPUVM::UserTranslationGen, gem5::AMDGPUVM::MMHUBTranslationGen, gem5::AMDGPUVM::GARTTranslationGen, gem5::AMDGPUVM::AGPTranslationGen, and gem5::BaseMMU::MMUTranslationGen.

Referenced by gem5::TranslationGenConstIterator::update().

Friends And Related Function Documentation

TranslationGenConstIterator

friend class TranslationGenConstIterator

friend

A const iterator class is provided so this generator can be used in a range based for loop.

When incremented, the iterator will either reattempt a translation that faulted earlier, or if there was no fault, will advance by "size" bytes and perform the translation of the next chunk.

Definition at line 121 of file translation_gen.hh.

Member Data Documentation

_size

Addr gem5::TranslationGen::_size

protected

Definition at line 97 of file translation_gen.hh.

Referenced by size().

_start

Addr gem5::TranslationGen::_start

protected

Definition at line 96 of file translation_gen.hh.

Referenced by start().

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

• mem/translation_gen.hh