luxos/Kernel/memory/mem-paging.c
Tiberiu Chibici caa7718af9 [GOOD] BUILD 0.1.0.551 DATE 9/03/2011 AT 9:25 AM
====================================================
Mainly changed: HAL.FSs
+ Updated 'mount' call in floppy driver, now done after controller is
initialized
+ Added 'detect' function for FAT file systems
+ Implemented 'initdr' driver, however still bugged
+ Improved logger
2021-09-14 18:51:43 +03:00

75 lines
1.8 KiB
C

/*
* memory-vi.c
*
* Created on: Aug 23, 2011
* Author: Tiberiu
*/
#include <memory-add.h>
#include <stdio.h>
/*******************************
* Data *
*******************************/
PageDirectory* CurrentDirectory;
PageDirectory* KernelDirectory;
/*******************************
* Useful routines *
*******************************/
void PagingInitialize(uint32 kernel_used)
{
Log("Mem", "Virtual memory manager initialization started. End of kernel = 0x%x\n", kernel_used);
PageDirectory* kernelPd = (PageDirectory*) kmalloc_a(sizeof(PageDirectory));
memset(kernelPd, 0, sizeof(PageDirectory));
CurrentDirectory = kernelPd;
KernelDirectory = kernelPd;
uint32 i;
for (i = 0; i < kernel_used; i+=0x1000)
MemPhAllocFrame(PagingGetPage(i, 1, kernelPd), 0, 0);
Log("Mem", "Identity mapped first 0x%x bytes.\n", kernel_used);
for (i = KERNEL_HEAP_START; i < KERNEL_HEAP_END; i+=0x1000)
MemPhAllocFrame(PagingGetPage(i, 1, kernelPd), 1, 1);
Log("Mem", "Mapped kernel space.\n");
PagingSwitchPageDirectory (kernelPd);
}
void PagingSwitchPageDirectory (PageDirectory* dir)
{
CurrentDirectory = dir;
asm volatile ("mov %0, %%cr3":: "r"(&dir->TablesPhysical));
uint32 cr0;
asm volatile ("mov %%cr0, %0": "=r"(cr0));
cr0 |= 0x80000000;
asm volatile ("mov %0, %%cr0":: "r"(cr0));
Log("Mem", "Enabled paging.\n");
}
Page* PagingGetPage(uint32 addr, uint8 make, PageDirectory* dir)
{
addr >>= 12;
uint32 tableIndex = addr >> 10;
if (dir->Tables[tableIndex])
return &dir->Tables[tableIndex]->Pages[addr&0x3ff];
else if (make)
{
uint32 temp;
dir->Tables[tableIndex] = (PageTable*)kmalloc_ap(sizeof(PageTable), &temp);
memset (dir->Tables[tableIndex], 0, 0x1000);
dir->TablesPhysical[tableIndex] = temp | 0x7;
return &dir->Tables[tableIndex]->Pages[addr&0x3ff];
}
else return 0;
}