gdt.h File Reference

The Global Descriptor Table (GDT). More...

#include "types.h"

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Classes
struct	GDT::SegmentDescriptor.__unnamed32__
	Fields specific for Data Segment (for debugging purposes) More...

Namespaces
namespace	GDT
	Abstracts the GDT that, primarily, contains descriptors to memory segments.

Enumerations
enum	GDT::Segments {   GDT::SEGMENT_NULL = 0 ,   GDT::SEGMENT_KERNEL_CODE ,   GDT::SEGMENT_KERNEL_DATA }
enum	GDT::Granularity {   GDT::GRANULARITY_BYTES = 0 ,   GDT::GRANULARITY_4KBLOCK = 1 }
	Unit of the segment limit. More...
enum	GDT::DescriptorType {   GDT::DESCRIPTOR_SYSTEM = 0 ,   GDT::DESCRIPTOR_CODEDATA = 1 }
	Descriptor type. More...
enum	GDT::Size {   GDT::SIZE_16BIT = 0 ,   GDT::SIZE_32BIT = 2 ,   GDT::SIZE_64BIT_CODE = 1 ,   GDT::SIZE_64BIT_DATA = 0 }
	Address width. More...

Detailed Description

The Global Descriptor Table (GDT).

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Class Documentation

GDT::SegmentDescriptor.__unnamed32__

struct GDT::SegmentDescriptor.__unnamed32__

Fields specific for Data Segment (for debugging purposes)

See also

ISDMv3, 3.4.5.1; Code- and Data-Segment Descriptor Types

Class Members
uint64_t	__pad0__: 40	Ignored (set via limit_low and base_low)
bool	data_accessed: 1	If set, the data segment was used since the last reset of this value.
bool	writeable: 1	If set, data is writable (otherwise read only)
bool	expand_down: 1	Growing direction for dynamically growing segments.
bool	notData: 1	Has to be cleared (false)
uint64_t	__pad1__: 9	Ignored (set via privilege_level ... available)
uint64_t	reserved: 1	Reserved, always set to 0!
bool	big: 1	Size of the stack pointer (false = 16 bit, true = 32 bit) Warning Has a different meaning in case expand_down is set to 1.
uint64_t	__pad2__: 0	Remainder ignored.