luxos/Kernel/memory/mem-phys.c~
Tiberiu Chibici 913e65b856 [GOOD] BUILD 0.1.0.450 DATE 8/29/2011 AT 10:30 AM
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+ Changed 'align 0x4' line above multiboot header in loader.asm to
'align 4'
+ Removed -e option for echo in build.sh
+ Modified build.sh for linux
+ Fixed triple fault when enabling paging
+ Fixed page faults at memory manager initialization
+ Fixed 'mem' console function
+ Added more info about page fault at crash screen
+ Added Panic() macro
+ Added verbose mode for memory manager

[ BAD] BUILD 0.1.0.390 DATE 8/27/2011 AT 10:54 PM
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+ Added stdlib routines, separated in different files
+ Rewritten physical memory manager
+ Added virtual mem manager
+ Added memory allocation/freeing
+ Added memory library
+ Added temporary allocation (at end of kernel), until paging is started
- Removed functionality from debug console function 'mem'
- Removed system.h, the one remaining function now in stdio.h
2021-09-14 18:48:57 +03:00

110 lines
2.3 KiB
C

/*
* mem-phys.c
*
* Created on: Aug 27, 2011
* Author: Tiberiu
*/
#include <memory-add.h>
uint32* FrameMap;
uint32 TotalFrames;
uint32 TotalMemory;
uint32 UsedFrames;
inline void ConvertIndexToFrame (uint32 index, uint32* address, uint32* offset)
{
*address = (index >> 5);
*offset = index & 0x1f;
}
inline uint32 ConvertFrameToIndex (uint32 address, uint32 offset)
{
return (address<<5) | offset;
}
void MemPhSetFrame (uint32 frame, uint8 value)
{
uint32 addr, off;
ConvertIndexToFrame(frame, &addr, &off);
if (value) {
if ((FrameMap[addr] & (1<<off)) == 0) UsedFrames++;
FrameMap[addr] |= 1<<off;
}
else {
if (FrameMap[addr] & (1<<off)) UsedFrames--;
FrameMap[addr] &= ~(1<<off);
}
}
uint32 MemPhGetFrame (uint32 frame)
{
uint32 addr, off;
ConvertIndexToFrame(frame, &addr, &off);
return FrameMap[addr] & (1<<off);
}
uint32 MemPhFindFreeFrame()
{
uint32 addr, pos;
for (addr = 0; addr < TotalFrames >> 5; addr++)
if (FrameMap[addr] != 0xffffffff)
{
for (pos = 0; (FrameMap[addr] & (1<<pos)) != 0; pos++) ;
return ConvertFrameToIndex(addr, pos);
}
return 0xffffffff;
}
void MemPhAllocFrame(Page* page, uint8 isKernel, uint8 isWriteable)
{
if ((*page & PageFrame) != 0) return;
uint32 free = MemPhFindFreeFrame();
if (free == 0xffffffff) {
Panic("%#Failed allocation free=0x%x page=0x%x\n", ColorRed, free, *page);
return;
}
MemPhSetFrame(free, 1);
*page |= PagePresent;
*page |= (isKernel) ? 0 : PageUser;
*page |= (isWriteable) ? PageWriteable : 0;
*page |= (free<<12) & PageFrame;
}
void MemPhFreeFrame(Page* page)
{
uint32 frame = *page & PageFrame;
if (!frame) return;
MemPhSetFrame(frame, 0);
*page &= ~PageFrame;
}
void MemPhInitialize(uint32 SystemMemoryKb)
{
LogMem("Starting physical memory manager...\n");
TotalFrames = SystemMemoryKb >> 2;
TotalMemory = SystemMemoryKb;
FrameMap = (uint32*) kmalloc(sizeof(uint32) * (1 + (TotalFrames>>5)));
memset(FrameMap, 0, sizeof(uint32) * (1 + (TotalFrames>>5)));
LogMem("%#Started physical memory manager ok!, found %ukb\n", ColorLightGreen, SystemMemoryKb);
}
void MemPhReserveFrames (uint32 address, uint32 length)
{
address >>= 12;
length = (length>>12) + ((length & 0xfff) > 0);
uint32 end = address + length;
for (; address < end ; address++)
MemPhSetFrame(address, 1);
}