Cucumber/Kernel/include/Tier0/paging.h

89 lines
2.6 KiB
C

#ifndef __PAGING_H__
#define __PAGING_H__
#include "types.h"
#include "load_context.h"
// Some helpful macros
#define PAGING_GET_PML4_INDEX(x) (((u64)x >> 39) & 0x1FF)
#define PAGING_GET_PDP_INDEX(x) (((u64)x >> 30) & 0x1FF)
#define PAGING_GET_DIR_INDEX(x) (((u64)x >> 21) & 0x1FF)
#define PAGING_GET_TAB_INDEX(x) (((u64)x >> 12) & 0x1FF)
#define PAGING_GET_PAGE_OFFSET(x) (x & 0xFFF)
// Intel-defined entries - strict!
struct S_PAGING_TAB_ENTRY {
u8 Present : 1;
u8 RW : 1;
u8 User : 1;
u8 Accessed : 1;
u8 Misc : 8;
u64 Physical : 40; // The physical address is limited by MAXPHYADDR
u16 Zero : 12;
} __attribute__((packed));
typedef struct S_PAGING_TAB_ENTRY T_PAGING_TAB_ENTRY;
struct S_PAGING_DIR_ENTRY {
u8 Present : 1;
u8 RW : 1;
u8 User : 1;
u8 Accessed : 1;
u8 Misc : 8;
u64 Physical : 40; // The physical address is limited by MAXPHYADDR
u64 Zero : 12;
} __attribute__((packed));
typedef struct S_PAGING_DIR_ENTRY T_PAGING_DIR_ENTRY;
struct S_PAGING_PDP_ENTRY {
u8 Present : 1;
u8 RW : 1;
u8 User : 1;
u8 Accessed : 1;
u8 Misc : 8;
u64 Physical : 40; // The physical address is limited by MAXPHYADDR
u64 Zero : 12;
} __attribute__((packed));
typedef struct S_PAGING_PDP_ENTRY T_PAGING_PDP_ENTRY;
struct S_PAGING_ML4_ENTRY {
u8 Present : 1;
u8 RW : 1;
u8 User : 1;
u8 Accessed : 1;
u8 Misc : 8;
u64 Physical : 40; // The physical address is limited by MAXPHYADDR
u64 Zero : 12;
} __attribute__((packed));
typedef struct S_PAGING_ML4_ENTRY T_PAGING_ML4_ENTRY;
// OS-defined structures
typedef struct {
T_PAGING_TAB_ENTRY Entries[512];
} __attribute__((packed)) T_PAGING_TAB;
typedef struct {
T_PAGING_DIR_ENTRY Entries[512]; // For use by the CPU
} __attribute__((packed)) T_PAGING_DIR;
typedef struct {
T_PAGING_PDP_ENTRY Entries[512]; // For use by the CPU
} __attribute__((packed)) T_PAGING_PDP;
typedef struct {
T_PAGING_ML4_ENTRY Entries[512]; // For use by the CPU
} __attribute__((packed)) T_PAGING_ML4;
// Generic funcitons
T_PAGING_ML4 * paging_get_ml4(void);
void paging_set_ml4(u64 ML4Physical);
// Management of kernel paging structures
void paging_kernel_init(void);
// Map a 4k page from Physical to Virtual. AccessBits is undefined right now.
void paging_map_page(u64 Virtual, u64 Physical, void *AccessBits);
// Map an arbitrary Size range from Physical to Virtual. Must still be kinda aligned.
void paging_map_area(u64 PhysicalStart, u64 VirtualStart, u64 Size, void *AccessBits);
#endif