Kernel/arch/amd64/cpu/gdt.hpp

68 lines
2.1 KiB
C++

/*
This file is part of Fennix Kernel.
Fennix Kernel is free software: you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation, either version 3 of
the License, or (at your option) any later version.
Fennix Kernel is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Fennix Kernel. If not, see <https://www.gnu.org/licenses/>.
*/
#ifndef __FENNIX_KERNEL_GDT_H__
#define __FENNIX_KERNEL_GDT_H__
#include <types.h>
#include <cpu/x86/x64/SegmentDescriptors.hpp>
namespace GlobalDescriptorTable
{
struct TaskStateSegment
{
uint32_t Reserved0 __aligned(16);
uint64_t StackPointer[3];
uint64_t Reserved1;
uint64_t InterruptStackTable[7];
uint64_t Reserved2;
uint16_t Reserved3;
uint16_t IOMapBaseAddressOffset;
} __packed;
struct GlobalDescriptorTableEntries
{
uint64_t Null;
CodeSegmentDescriptor Code;
DataSegmentDescriptor Data;
DataSegmentDescriptor UserData;
CodeSegmentDescriptor UserCode;
SystemSegmentDescriptor TaskStateSegment;
} __packed;
struct GlobalDescriptorTableDescriptor
{
uint16_t Limit;
GlobalDescriptorTableEntries *BaseAddress;
} __packed;
extern void *CPUStackPointer[];
extern TaskStateSegment tss[];
void Init(int Core);
void SetKernelStack(void *Stack);
void *GetKernelStack();
}
#define GDT_KERNEL_CODE offsetof(GlobalDescriptorTable::GlobalDescriptorTableEntries, Code)
#define GDT_KERNEL_DATA offsetof(GlobalDescriptorTable::GlobalDescriptorTableEntries, Data)
#define GDT_USER_CODE (offsetof(GlobalDescriptorTable::GlobalDescriptorTableEntries, UserCode) | 3)
#define GDT_USER_DATA (offsetof(GlobalDescriptorTable::GlobalDescriptorTableEntries, UserData) | 3)
#define GDT_TSS (offsetof(GlobalDescriptorTable::GlobalDescriptorTableEntries, TaskStateSegment) | 3)
#endif // !__FENNIX_KERNEL_GDT_H__