mirror of
https://gitlab.os-k.eu/os-k-team/os-k.git
synced 2023-08-25 14:03:10 +02:00
109 lines
2.6 KiB
C
109 lines
2.6 KiB
C
#include <kernel.h>
|
|
#include <init/boot.h>
|
|
#include <ex/malloc.h>
|
|
#include <mm/mm.h>
|
|
|
|
#define PAGESIZE (4 * KB)
|
|
|
|
|
|
// Page directory pointer offset
|
|
typedef ulong pdpe_t;
|
|
|
|
// Page directory offset
|
|
typedef ulong pde_t;
|
|
|
|
// Page table entry
|
|
typedef ulong pte_t;
|
|
|
|
// paging.asm
|
|
void MmLoadPML4(void *);
|
|
void MmEnableWriteProtect(void);
|
|
void MmDisableWriteProtect(void);
|
|
|
|
enum
|
|
{
|
|
MF_PRESENT = 1 << 0,
|
|
MF_READWRITE = 1 << 1,
|
|
MF_USERMODE = 1 << 2,
|
|
MF_WRITETHR = 1 << 3,
|
|
MF_CACHEDIS = 1 << 4,
|
|
MF_ACCESSED = 1 << 5,
|
|
MF_DIRTY = 1 << 6,
|
|
MF_HUGE = 1 << 7,
|
|
MF_NX = 1 << 31
|
|
};
|
|
|
|
#define RAM_MAX 32
|
|
#define NB_4K 150
|
|
// * 2 MB
|
|
|
|
//-----------
|
|
|
|
volatile pdpe_t MmPML4[512] __attribute__((__aligned__(4096)));
|
|
|
|
volatile pde_t MmPDP[512] __attribute__((__aligned__(4096)));
|
|
|
|
volatile pde_t MmPD[512 * RAM_MAX] __attribute__((__aligned__(4096)));;
|
|
|
|
volatile pte_t MmPT[512 * NB_4K] __attribute__((__aligned__(4096)));;
|
|
|
|
volatile ulong MmStackGuards[2] = { 0 };
|
|
|
|
//
|
|
// Creates our new page table structure and loads it
|
|
void MmInitPaging(void)
|
|
{
|
|
extern MemoryMap_t memoryMap;
|
|
ulong phRamSize = memoryMap.freeRamSize + memoryMap.nonfreeRamSize;
|
|
|
|
memzero((void *)&MmPML4[0], sizeof(MmPML4));
|
|
memzero((void *)&MmPDP[0], sizeof(MmPDP));
|
|
memzero((void *)&MmPD[0], sizeof(MmPD));
|
|
memzero((void *)&MmPT[0], sizeof(MmPT));
|
|
|
|
for (volatile ulong i = 0; i < 512 * NB_4K; i++) {
|
|
// STACK GUARD PAGE
|
|
if ((ulong)(i*4096) == (ulong)BtLoaderInfo.stackEndAddr) {
|
|
MmPT[i] = ((ulong)(i*4096));
|
|
MmStackGuards[0] = i;
|
|
continue;
|
|
}
|
|
|
|
// ENOMEM like
|
|
if ((ulong)(i*4096) > (ulong)phRamSize) {
|
|
break;
|
|
}
|
|
|
|
// STACK GARD PAGE
|
|
if ((ulong)(i*4096) == (ulong)BtLoaderInfo.kernelEndAddr) {
|
|
MmPT[i] = ((ulong)(i*4096));
|
|
MmStackGuards[1] = i;
|
|
continue;
|
|
}
|
|
|
|
MmPT[i] = ((ulong)(i*4096)) | MF_PRESENT | MF_READWRITE;
|
|
}
|
|
|
|
for (volatile ulong i = 0; i < NB_4K; i++) {
|
|
MmPD[i] = (ulong)(&MmPT[i*512])| MF_PRESENT | MF_READWRITE;
|
|
}
|
|
|
|
for (volatile ulong i = NB_4K; i < 512 * RAM_MAX; i++) {
|
|
// ENOMEM like
|
|
if ((ulong)(i* 2048 * 1024) > (ulong)phRamSize) {
|
|
break;
|
|
}
|
|
|
|
MmPD[i] = 0;
|
|
MmPD[i] = ((ulong)(i* 2048 * 1024)) | MF_PRESENT | MF_READWRITE | MF_HUGE;
|
|
}
|
|
|
|
for (volatile int i = 0; i < RAM_MAX; i++) {
|
|
MmPDP[i] = (ulong)(&MmPD[i*512])| MF_PRESENT | MF_READWRITE;
|
|
}
|
|
|
|
MmPML4[0] = (ulong)(&MmPDP[0])| MF_PRESENT | MF_READWRITE;
|
|
|
|
MmLoadPML4((void *)MmPML4);
|
|
}
|