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Update GDT & IDT structures

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This commit is contained in:
Alex
2023-08-25 02:53:35 +03:00
parent 05610c7e7a
commit 622214003f
4 changed files with 270 additions and 514 deletions
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277
Architecture/amd64/cpu/gdt.hpp
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@@ -19,100 +19,10 @@
#define __FENNIX_KERNEL_GDT_H__
#include <types.h>
#include <cpu/x86/x64/SegmentDescriptors.hpp>
namespace GlobalDescriptorTable
{
struct TaskStateSegmentEntry
{
/* LOW */
uint16_t Limit;
uint16_t BaseLow;
uint8_t BaseMiddle;
union GlobalDescriptorTableAccess
{
struct
{
/**
* Access bit.
*
* @note The CPU sets this bit to 1 when the segment
* is accessed.
*/
uint8_t A : 1;
/**
* Readable bit for code segments, writable bit for data
* segments.
*
* Code Segment:
* This bit must be 1 for the segment to be readable.
*
* Data Segment:
* This bit must be 1 for the segment to be writable.
*/
uint8_t RW : 1;
/**
* Direction bit for data segments, conforming bit for
* code segments.
*
* Code Segment:
* This bit must be 1 for code in the segment to be
* able to be executed from an equal or lower privilege
* level.
*
* Data Segment:
* This bit must be 1 for the segment to grow up (higher
* addresses).
*/
uint8_t DC : 1;
/**
* Executable bit.
*
* This bit must be 1 for code-segment descriptors.
*
* This bit must be 0 for data-segment and system
* descriptors.
*/
uint8_t E : 1;
/**
* Descriptor type.
*
* This bit must be 0 for system descriptors.
*
* This bit must be 1 for code or data segment
* descriptor.
*/
uint8_t S : 1;
/**
* Descriptor privilege level.
*
* This field determines the privilege level of the
* segment.
*
* 0 = kernel mode
* 3 = user mode
*/
uint8_t DPL : 2;
/**
* Present bit.
*
* This bit must be 1 for all valid descriptors.
*/
uint8_t P : 1;
} __packed;
uint8_t Raw : 8;
} Access;
uint8_t Granularity;
uint8_t BaseHigh;
/* HIGH */
uint32_t BaseUpper;
uint32_t Reserved;
} __packed;
struct TaskStateSegment
{
@@ -125,189 +35,20 @@ namespace GlobalDescriptorTable
uint16_t IOMapBaseAddressOffset;
} __packed;
struct GlobalDescriptorTableEntry
{
/**
* Limit 0:15
*/
uint16_t Limit0 : 16;
/**
* Low Base 0:15
*/
uint16_t BaseLow : 16;
/**
* Middle Base 16:23
*/
uint8_t BaseMiddle : 8;
/**
* Access
*/
union GlobalDescriptorTableAccess
{
struct
{
/**
* Access bit.
*
* @note The CPU sets this bit to 1 when the segment
* is accessed.
*/
uint8_t A : 1;
/**
* Readable bit for code segments, writable bit for
* data segments.
*
* Code Segment:
* This bit must be 1 for the segment to be readable.
*
* Data Segment:
* This bit must be 1 for the segment to be writable.
*/
uint8_t RW : 1;
/**
* Direction bit for data segments, conforming bit for
* code segments.
*
* Code Segment:
* This bit must be 1 for code in the segment to be able
* to be executed from an equal or lower privilege level.
*
* Data Segment:
* This bit must be 1 for the segment to grow up (higher
* addresses).
*/
uint8_t DC : 1;
/**
* Executable bit.
*
* This bit must be 1 for code-segment descriptors.
*
* This bit must be 0 for data-segment and
* system descriptors.
*/
uint8_t E : 1;
/**
* Descriptor type.
*
* This bit must be 0 for system descriptors.
*
* This bit must be 1 for code or data segment
* descriptor.
*/
uint8_t S : 1;
/**
* Descriptor privilege level.
*
* This field determines the privilege level of the
* segment.
*
* 0 = kernel mode
* 3 = user mode
*/
uint8_t DPL : 2;
/**
* Present bit.
*
* This bit must be 1 for all valid descriptors.
*/
uint8_t P : 1;
} __packed;
uint8_t Raw : 8;
} Access;
// /** Limit 16:19 */
// uint16_t Limit1 : 4;
/**
* Flags
*/
union GlobalDescriptorTableFlags
{
struct
{
/* FIXME: Without this, the kernel crashes. */
uint8_t Reserved : 4;
/**
* Available bit.
*
* This bit is available for use by system software.
*/
uint8_t AVL : 1;
/**
* Long mode.
*
* If the long mode bit is clear, the segment is in
* 32-bit protected mode.
*
* If the long mode bit is set, the segment is in
* 64-bit long mode.
*/
uint8_t L : 1;
/**
* Size flag.
*
* If the size bit is clear, the segment is in
* 16-bit protected mode.
*
* If the size bit is set, the segment is in
* 32-bit protected mode.
*/
uint8_t DB : 1;
/**
* Granularity bit.
*
* If the granularity bit is clear, the segment limit
* is in 1 B blocks.
*
* If the granularity bit is set, the segment limit is
* in 4 KiB blocks.
*/
uint8_t G : 1;
} __packed;
uint8_t Raw : 8;
} Flags;
/**
* High Base 24:31
*/
uint8_t BaseHigh : 8;
} __packed;
struct GlobalDescriptorTableEntries
{
GlobalDescriptorTableEntry Null;
GlobalDescriptorTableEntry Code;
GlobalDescriptorTableEntry Data;
GlobalDescriptorTableEntry UserData;
GlobalDescriptorTableEntry UserCode;
TaskStateSegmentEntry TaskStateSegment;
uint64_t Null;
CodeSegmentDescriptor Code;
DataSegmentDescriptor Data;
DataSegmentDescriptor UserData;
CodeSegmentDescriptor UserCode;
SystemSegmentDescriptor TaskStateSegment;
} __packed;
struct GlobalDescriptorTableDescriptor
{
/**
* GDT entries length
*/
uint16_t Length;
/**
* GDT entries address
*/
GlobalDescriptorTableEntries *Entries;
uint16_t Limit;
GlobalDescriptorTableEntries *BaseAddress;
} __packed;
extern void *CPUStackPointer[];