rex::kernel::GuestMemory Class Reference

#include <rex/kernel/guest_memory.h>

Public Member Functions
	GuestMemory (const GuestMemory &)=delete
GuestMemory &	operator= (const GuestMemory &)=delete
Result< void >	CopyFrom (u32 address, std::span< std::byte > out) const
Result< void >	CopyTo (u32 address, std::span< const std::byte > data)
Result< std::span< const std::byte > >	GetReadOnlySpan (u32 address, u32 length) const
Result< std::span< std::byte > >	GetWritableSpan (u32 address, u32 length)
template<typename T> requires std::is_trivially_copyable_v<T>
Result< T >	Load (u32 address) const
template<typename T> requires std::is_trivially_copyable_v<T>
Result< void >	Store (u32 address, const T &value)
Result< std::string >	ReadString (u32 address, u32 max_length=4096) const
Result< std::u16string >	ReadString16 (u32 address, u32 max_length=4096) const
Result< u32 >	Allocate (u32 size, u32 alignment, GuestProtect protect, GuestHeap heap=GuestHeap::kTitle)
Result< void >	Free (u32 address)
Result< void >	Protect (u32 address, u32 length, GuestProtect protect)
kernel::MemoryView	GetView () const
Result< u32 >	HostToGuest (const void *host) const

Friends
class	TitleRuntime
class	kernel::GuestAllocator
class	kernel::TitleState

Detailed Description

Checked guest virtual memory, used by everything except recompiled code. A call whose range is not mapped with the needed access returns a kMemory error and changes nothing. Spans stay valid until TitleRuntime::Unload.

Member Function Documentation

Allocate()

Result< u32 > rex::kernel::GuestMemory::Allocate ( u32 size, u32 alignment, GuestProtect protect, GuestHeap heap = GuestHeap::kTitle )

nodiscard

Allocates guest memory.

Parameters

size	The size in bytes.
alignment	A power of two, at least 4096 for title memory.
heap	The heap, title memory by default. Physical is the 64 KiB window at 0xA0000000.

Returns

The address, or a kMemory error.

CopyFrom()

Result< void > rex::kernel::GuestMemory::CopyFrom ( u32 address, std::span< std::byte > out ) const

nodiscard

Copies guest memory into a buffer.

Parameters

out	The buffer to fill. Its size is the length.

Returns

Ok, or a kMemory error.

CopyTo()

Result< void > rex::kernel::GuestMemory::CopyTo ( u32 address, std::span< const std::byte > data )

nodiscard

Copies bytes into guest memory.

Parameters

data	The bytes to copy.

Returns

Ok, or a kMemory error when any byte is not mapped writable.

Free()

Result< void > rex::kernel::GuestMemory::Free ( u32 address )

nodiscard

Frees memory from Allocate, from either heap.

Parameters

address

The address Allocate returned.

Returns

Ok, or a kMemory error.

GetReadOnlySpan()

Result< std::span< const std::byte > > rex::kernel::GuestMemory::GetReadOnlySpan ( u32 address, u32 length ) const

nodiscard

Returns guest memory to read in place, or a kMemory error.

GetView()

kernel::MemoryView rex::kernel::GuestMemory::GetView ( ) const

nodiscard

Returns an address view usable from any thread until TitleRuntime::Unload.

GetWritableSpan()

Result< std::span< std::byte > > rex::kernel::GuestMemory::GetWritableSpan ( u32 address, u32 length )

nodiscard

Returns guest memory to write in place, or a kMemory error when any byte is not mapped writable.

HostToGuest()

Result< u32 > rex::kernel::GuestMemory::HostToGuest ( const void * host ) const

nodiscard

Translates a host pointer inside guest memory to its guest address.

Parameters

host	A pointer, such as the data of a span from GetWritableSpan.

Returns

The guest address, or a kMemory error when the pointer is outside guest memory.

Load()

template<typename T>
requires std::is_trivially_copyable_v<T>

Result< T > rex::kernel::GuestMemory::Load ( u32 address ) const

nodiscard

Reads a guest value.

Template Parameters

T	A trivially copyable guest type, such as be_u32 or a struct of be_ fields.

Returns

A copy, or a kMemory error.

Reads a guest value.

Returns

A copy, or a kMemory error.

Protect()

Result< void > rex::kernel::GuestMemory::Protect ( u32 address, u32 length, GuestProtect protect )

nodiscard

Changes the access of mapped pages. The range covers every page from the one holding the first byte to the one holding the last.

Returns

Ok, or a kMemory error when any page is not mapped.

ReadString()

Result< std::string > rex::kernel::GuestMemory::ReadString ( u32 address, u32 max_length = 4096 ) const

nodiscard

Reads a zero terminated 8 bit string.

Parameters

max_length

The character limit when no terminator comes first.

Returns

The string, or a kMemory error.

ReadString16()

Result< std::u16string > rex::kernel::GuestMemory::ReadString16 ( u32 address, u32 max_length = 4096 ) const

nodiscard

Reads a zero terminated big endian UTF-16 string.

Parameters

max_length

The character limit when no terminator comes first.

Returns

The string in host byte order, or a kMemory error.

Store()

template<typename T>
requires std::is_trivially_copyable_v<T>

Result< void > rex::kernel::GuestMemory::Store ( u32 address, const T & value )

nodiscard

Writes a guest value.

Template Parameters

T	A trivially copyable guest type, such as be_u32 or a struct of be_ fields.

Returns

Ok, or a kMemory error.

Writes a guest value.

Returns

Ok, or a kMemory error.

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

• rex/kernel/guest_memory.h