Nigel/BarinkOS
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Merge into main the new state of the operating system/kernel #1

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Nigel wants to merge 120 commits from dev into main
pull from: dev
merge into: Nigel:main
Conversation 0 Commits 120 Files Changed 146 +472 -426
24 changed files with 472 additions and 426 deletions
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Showing only changes of commit b4cff3e667 - Show all commits

11
Makefile
View File

@ -5,7 +5,7 @@ CC = ${HOME}/opt/cross/bin/i686-elf-gcc
CPP = ${HOME}/opt/cross/bin/i686-elf-g++
CFLAGS = -ffreestanding -O2 -Wall -Wextra
OFILES =$(BUILD_DIR)/boot.o $(BUILD_DIR)/kterm.o $(BUILD_DIR)/kernel.o $(BUILD_DIR)/pit.o $(BUILD_DIR)/time.o $(BUILD_DIR)/keyboard.o $(BUILD_DIR)/PhysicalMemoryManager.o $(BUILD_DIR)/io.o $(BUILD_DIR)/PageDirectory.o $(BUILD_DIR)/gdtc.o $(BUILD_DIR)/idt.o $(BUILD_DIR)/pic.o $(BUILD_DIR)/sv-terminal.o $(BUILD_DIR)/string.o $(BUILD_DIR)/PageFrameAllocator.o
OFILES =$(BUILD_DIR)/boot.o $(BUILD_DIR)/kterm.o $(BUILD_DIR)/kernel.o $(BUILD_DIR)/memory.o $(BUILD_DIR)/pit.o $(BUILD_DIR)/time.o $(BUILD_DIR)/keyboard.o $(BUILD_DIR)/io.o $(BUILD_DIR)/gdtc.o $(BUILD_DIR)/idt.o $(BUILD_DIR)/pic.o $(BUILD_DIR)/sv-terminal.o $(BUILD_DIR)/string.o
SRC_DIR = src
BUILD_DIR = build
@ -54,7 +54,7 @@ $(BUILD_DIR)/kterm.o:
$(CPP) -c $(SRC_DIR)/kernel/tty/kterm.cpp -o $(BUILD_DIR)/kterm.o $(CFLAGS) -fno-exceptions -fno-rtti
$(BUILD_DIR)/boot.o:
$(AS) $(SRC_DIR)/kernel//boot.S -o $(BUILD_DIR)/boot.o
$(AS) $(SRC_DIR)/kernel/boot.s -o $(BUILD_DIR)/boot.o
$(BUILD_DIR)/crti.o:
$(AS) $(SRC_DIR)/kernel/crti.s -o $(BUILD_DIR)/crti.o
@ -65,8 +65,6 @@ $(BUILD_DIR)/crtn.o:
$(BUILD_DIR)/io.o:
$(CPP) -c $(SRC_DIR)/kernel/io.cpp -o $(BUILD_DIR)/io.o $(CFLAGS) -fno-exceptions -fno-rtti
$(BUILD_DIR)/PageDirectory.o:
$(CPP) -c $(SRC_DIR)/kernel/memory/PageDirectory.cpp -o $(BUILD_DIR)/PageDirectory.o $(CFLAGS) -fno-exceptions -fno-rtti
$(BUILD_DIR)/idt.o:
$(CPP) -c $(SRC_DIR)/kernel/idt/idt.cpp -o $(BUILD_DIR)/idt.o $(CFLAGS) -fno-exceptions -fno-rtti
@ -81,8 +79,6 @@ $(BUILD_DIR)/pic.o:
$(BUILD_DIR)/string.o:
$(CC) -c $(SRC_DIR)/libc/include/string.c -o $(BUILD_DIR)/string.o $(CFLAGS) -std=gnu99
$(BUILD_DIR)/PhysicalMemoryManager.o:
$(CPP) -c $(SRC_DIR)/kernel/memory/PhysicalMemoryManager.cpp -o $(BUILD_DIR)/PhysicalMemoryManager.o $(CFLAGS) -fno-exceptions -fno-rtti
$(BUILD_DIR)/pit.o:
$(CPP) -c $(SRC_DIR)/kernel/pit.cpp -o $(BUILD_DIR)/pit.o $(CFLAGS) -fno-exceptions -fno-rtti
@ -97,3 +93,6 @@ $(BUILD_DIR)/time.o:
$(BUILD_DIR)/sv-terminal.o:
$(CPP) -c $(SRC_DIR)/kernel/sv-terminal/superVisorTerminal.cpp -o $(BUILD_DIR)/sv-terminal.o $(CFLAGS) -fno-exceptions -fno-rtti
$(BUILD_DIR)/memory.o:
$(CPP) -c $(SRC_DIR)/kernel/memory/memory.cpp -o $(BUILD_DIR)/memory.o $(CFLAGS) -fno-exceptions -fno-rtti

3
README.md
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@ -19,7 +19,8 @@ Multiboot information can be read by the kernel.
________________________
### The goal
Writing a hobby operating system to better understand the basic building blocks of any operating system.
Writing a hobby operating system to better understand the basic building blocks of any operating system.Initially I'd like for my
operating system to be able to run bash.
________________________
### Operating System Technical specs/details

37
features.md
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@ -1,29 +1,30 @@
# TODO list
## Start planning
## Basics
<input type="checkbox" checked/> Setup Cross-Compiler \
<input type="checkbox" checked/> Multiboot to kernel \
<input type="checkbox" checked/> Printing string to the screen \
<input type="checkbox" checked/> Printing values/numbers to the screen (a.k.k itoa) \
<input type="checkbox" checked/> Printing values/numbers to the screen \
<input type="checkbox" checked/> Basic Terminal \
<input type="checkbox" checked/> Extend Multiboot implementation \
<input type="checkbox" checked/> Output to serial port \
<input type="checkbox" checked/> Move to protected mode \
<input type="checkbox" checked/> Enabel CMOS clock \
<input type="checkbox" /> Time measurement (PIC &| PIT) \
<input type="checkbox" checked/> Time measurement (PIC &| PIT) \
<input type="checkbox" /> Detect CPU speed \
<input type="checkbox" checked/> Interrupt / exception system (API) \
<input type="checkbox" checked/> Plan your memory map (virtual, and physical) : decide where you want the data to be. \
<input type="checkbox" checked/> PCI support \
<input type="checkbox" checked/> ATA PIO Mode support \
<input type="checkbox" checked/> FAT Filesystem \
<input type="checkbox" /> Virtual filesystem \
<input type="checkbox" checked/> Keyboard support ( P/S2 Keyboard) \
<input type="checkbox" checked/> Physical memory management \
<input type="checkbox" /> Paging \
<input type="checkbox" /> Virtual memory management \
<input type="checkbox" /> The heap: allocating memory at runtime (malloc and free) is almost impossible to go without. \
<input type="checkbox" /> Enable SIMD Extensions (SSE)
## Other features I am thinking of:
<input type="checkbox" /> PCI support \
<input type="checkbox" /> ATA PIO Mode support \
<input type="checkbox" /> USTAR Filesystem ( For its simplicity this is very likely the first filesystem the OS is going to support) \
<input type="checkbox" /> ACPI support ( Or some other basic way to support shutdown, reboot and possibly hibernation ) \
<input type="checkbox" /> ATAPI support \
<input type="checkbox" /> Keyboard support ( P/S2 Keyboard) \
<input type="checkbox" checked/> Memory Management (MMU)
<input type="checkbox" /> Hardware Management system
<input type="checkbox" /> Preemptive multi tasking \
<input type="checkbox" /> Processes \
<input type="checkbox" /> Threads
@ -32,9 +33,11 @@
<input type="checkbox" /> POSIX compliance (partially) \
<input type="checkbox" /> RPC - for interprocess communication \
<input type="checkbox" /> Sync primitives - Semaphores, Mutexes, spinlocks et al. \
<input type="checkbox" /> Basic Terminal \
<input type="checkbox" /> Extend hardware recognition ( CPU codename, memory, ATA harddisk, RAW diskSpace, CPU speed through SMBIOS et al. ) \
<input type="checkbox" /> ACPI support \
<input type="checkbox" /> ATAPI support \
## Optional
<input type="checkbox" /> Basic Window server/client \
## Support for more filesystems if I like the challenge in writing these ...
<input type="checkbox" /> FAT Filesystem \
<input type="checkbox" /> EXT2 Filesystem
<input type="checkbox" /> USTAR Filesystem \

5
src/grub.cfg
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@ -1,3 +1,8 @@
GRUB_DEFAULT=0
GRUB_TIMEOUT=-1
GRUB_HIDDEN_TIMEOUT=0
GRUB_HIDDEN_TIMEOUT_QUITE=true
menuentry "BarinkOS" {
multiboot /boot/myos.bin
}

0
src/kernel/boot.S → src/kernel/boot.s
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9
src/kernel/bootinfo.h Normal file
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@ -0,0 +1,9 @@
#pragma once
#include "memory/memoryinfo.h"
struct BootInfo{
const char* BootStructureID = "BarinkOS";
MemoryInfo* memory;
};

11
src/kernel/definitions.h Normal file
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@ -0,0 +1,11 @@
#pragma once
/**
* Kernel definitions
*/
#define __DEBUG__ false
#define KERNEL_VERSION 0
#define ARCHITECTURE "I386"

127
src/kernel/kernel.cpp
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@ -1,7 +1,12 @@
#include "kernel.h"
#define GB2 262144
extern "C" void kernel_main (void);
extern "C" void kernel_main (BootInfo* bootinfo) {
init_serial();
pit_initialise();
startSuperVisorTerminal(bootinfo);
}
extern "C" void early_main(unsigned long magic, unsigned long addr){
/**
@ -31,18 +36,76 @@
*/
multiboot_info_t* mbt = (multiboot_info_t*) addr;
/**
* Construct our own bootInfo structure
*/
BootInfo bootinfo = {};
/*
If we got a memory map from our bootloader we
should be parsing it to find out the memory regions available.
*/
if (CHECK_FLAG(mbt->flags, 6))
{
printf("Preliminary results mmap scan:\n");
mapMultibootMemoryMap(mbt);
PhysicalMemoryManager_initialise( mbt->mmap_addr, GB2/* Seriously dangerous hardcoded memory value*/);
PhysicalMemoryManager_initialise_available_regions(mbt->mmap_addr, mbt->mmap_addr + mbt->mmap_length);
PhysicalMemoryManager_deinitialise_kernel();
/*
Setup Physical memory managment
*/
MemoryInfo meminfo = {};
bootinfo.memory = &meminfo;
mapMultibootMemoryMap(bootinfo.memory , mbt);
printf("Memory size: 0x%x bytes\n", bootinfo.memory->TotalMemory );
PhysicalMemory memAlloc = PhysicalMemory{};
memAlloc.setup(bootinfo.memory );
/*
Mark already in use sections
*/
// Mark kernel memory as used
printf("Kernel Begin Pointer: 0x%x, Kernel end pointer: 0x%x\n", kernel_begin , kernel_end );
multiboot_memory_map_t *mmap = (multiboot_memory_map_t*) mbt->mmap_addr;
for (; (unsigned long) mmap < mbt->mmap_addr + mbt->mmap_length; mmap = (multiboot_memory_map_t *) ((unsigned long) mmap + mmap->size + sizeof(mmap->size))){
if ( mmap->type == MULTIBOOT_MEMORY_AVAILABLE){
} else{
printf("allocate region: 0x%x, size : 0x%x bytes\n", (unsigned) mmap->addr,(unsigned) mmap->len );
memAlloc.allocate_region((unsigned)mmap->addr , (unsigned)mmap->len);
}
}
printf("allocate region: 0x%x, size : 0x%x bytes\n", kernel_begin, kernel_end - kernel_begin );
memAlloc.allocate_region(kernel_end, kernel_end - kernel_begin);
// test alloc_block
uint8_t* memory = (uint8_t*) memAlloc.allocate_block();
printf("Got a new pointer: 0x%x\n", memory);
uint8_t* memory2 = (uint8_t*) memAlloc.allocate_block();
printf("Got a new pointer: 0x%x\n", memory2);
memAlloc.free_block((void*) memory);
uint8_t* newBlockPlse = (uint8_t*) memAlloc.allocate_block();
// memAlloc.free_block((void*) memory);
}
initGDT();
@ -54,55 +117,7 @@
CheckMBT( (multiboot_info_t *) addr);
kernel_main();
}
extern "C" void kernel_main (void) {
init_serial();
pit_initialise();
while (true){
printf("SUPERVISOR:>$ " );
int characterCount = 0;
char command[10] = "";
// NOTE: lets just show a kernel prompt
uint8_t ScanCode = getKey();
while( ScanCode != 0x1C )
{
char character = getASCIIKey();
kterm_put(character );
// wHAT THE HELL
if( characterCount < 10 ){
command[characterCount] = character;
characterCount++;
}
ScanCode = getKey();
}
printf("\n");
KeyHandled();
if ( strncmp("TIME", command , characterCount ) == 0 ) {
read_rtc();
printf( "UTC time: %02d-%02d-%02d %02d:%02d:%02d (Ticks: %06d)\n" ,year, month, day, hour, minute, second, pit_tick);
} else if(strncmp("TEST", command, characterCount) == 0){
// asm volatile ("MOV $4, %AX ; MOV $0, %BX ; DIV %BX"); // IRS 0
}
else{
printf("Unknown command\n");
}
delay(1000);
}
kernel_main(&bootinfo);
}

12
src/kernel/kernel.h
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@ -1,14 +1,20 @@
#pragma once
extern "C"{
extern "C"
{
#include "../libc/include/string.h"
}
#include "definitions.h"
#include "vga/VBE.h"
#include "tty/kterm.h"
#include "./bootloader/multiboot.h"
#include "bootinfo.h"
#include "memory/memory.h"
#include "memory/memoryinfo.h"
#include "bootcheck.h"
#include "memory/physical/PhysicalMemoryManager.h"
#include "memory/frames/PageFrameAllocator.h"
#include "gdt/gdtc.h"
#include "idt/idt.h"

24
src/kernel/kstructures/bitmap.h
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@ -13,26 +13,26 @@ inline void bitmap_unset(uint32_t* map , int index)
map[index/32] &= ~(1 << (index % 32));
}
inline int bitmap_first_unset( uint32_t* map , int size)
inline uint32_t bitmap_first_unset( uint32_t* map , int map_size)
{
uint32_t rem_bits = size % 32;
for(uint32_t i = 0; i < size/32; i++)
for ( int i = 0 ; i < map_size ; i ++ )
{
if(map[i] != 0xFFFFFFFF){
// a bit or more is set within this byte!
if( (map[i] & 0xFFFFFFFF) > 0 ){
// which bit is set?
for(int j = 0 ; j < 32 ; j++){
if(!(map[i] & (1<< j))){
if ( (map[i] & (0x00000001 << j)) > 0)
{
printf("Found bit: byte 0x%x , bit 0x%x\n", i , j);
return (i*32)+j;
}
}
}
}
if(rem_bits){
for(uint32_t j = 0; j < rem_bits; j++){
if(!(map[size/32] & (1 << j ))){
return size + j; // Original author divided size by 32 and then multiplied it by 32 which is a net zero calculation ?!?
}
}
}
return -1;

58
src/kernel/memory/PageDirectory.cpp
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@ -1,47 +1,43 @@
#include "PageDirectory.h"
#include <stdint.h>
void PageDirectory::enable()
{
void PageDirectory::enable(){
// https://wiki.osdev.org/Setting_Up_Paging
//set each entry to not present
int i;
for(i = 0; i < 1024; i++)
{
// This sets the following flags to the pages:
// Supervisor: Only kernel-mode can access them
// Write Enabled: It can be both read from and written to
// Not Present: The page table is not present
this->page_directory[i] = 0x00000002;
}
// int i;
// for(i = 0; i < 1024; i++)
// {
// // This sets the following flags to the pages:
// // Supervisor: Only kernel-mode can access them
// // Write Enabled: It can be both read from and written to
// // Not Present: The page table is not present
// this->page_directory[i] = 0x00000002;
// }
// holds the physical address where we want to start mapping these pages to.
// in this case, we want to map these pages to the very beginning of memory.
// // holds the physical address where we want to start mapping these pages to.
// // in this case, we want to map these pages to the very beginning of memory.
//we will fill all 1024 entries in the table, mapping 4 megabytes
for(unsigned int i = 0; i < 1024; i++)
{
// As the address is page aligned, it will always leave 12 bits zeroed.
// Those bits are used by the attributes ;)
first_page_table[i] = (i * 0x1000) | 3; // attributes: supervisor level, read/write, present.
}
// //we will fill all 1024 entries in the table, mapping 4 megabytes
// for(unsigned int i = 0; i < 1024; i++)
// {
// // As the address is page aligned, it will always leave 12 bits zeroed.
// // Those bits are used by the attributes ;)
// first_page_table[i] = (i * 0x1000) | 3; // attributes: supervisor level, read/write, present.
// }
// attributes: supervisor level, read/write, present
this->page_directory[0] = ((unsigned int)first_page_table) | 3;
// // attributes: supervisor level, read/write, present
// this->page_directory[0] = ((unsigned int)first_page_table) | 3;
printf("Enable Paging!\n");
loadPageDirectory(this->page_directory);
enablePaging();
}
/*
void IdentityPaging(uint32_t *first_pte, vaddr from, int size)
void PageDirectory::MapPhysicalToVirtualAddress ( address_t PAddress , address_t VAddress, uint32_t size )
{
from = from & 0xFFFFF000; // Discard the bits we don't want
for (; size > 0; from += 4096, first_pte++)
{
*first_pte = from | 1; // makr page present.
}
}
*/

19
src/kernel/memory/PageDirectory.h
View File

@ -1,17 +1,18 @@
#pragma once
#include <stdint.h>
extern "C" void loadPageDirectory (uint32_t* addr );
extern "C" void enablePaging();
typedef uintptr_t address_t;
#include "./memory.h"
#include "./../tty/kterm.h"
#define KB 1024
typedef uintptr_t address_t;
static const int MAX_PAGES = 1024 * KB; // 4GB , 4kB/page
static volatile address_t pmem_stack[MAX_PAGES];
static volatile address_t pmem_stack_top = MAX_PAGES; // top down allocation
extern "C" void loadPageDirectory (uint32_t* addr );
extern "C" void enablePaging();
struct page_directory_entry {};
struct page_table_entry{};
@ -21,8 +22,10 @@ struct page_table_entry{};
class PageDirectory {
public:
void enable ();
void MapPhysicalToVirtualAddress ( address_t PAddress , address_t VAddress, uint32_t size );
private:
uint32_t page_directory[1024] __attribute__((aligned(4096)));
uint32_t first_page_table[1024] __attribute__((aligned(4096)));
uint32_t page_directory[1024] __attribute__((aligned(4096))); // align on 4 kiloByte pages
uint32_t first_page_table[1024] __attribute__((aligned(4096))); // align on 4 kiloByte pages
};

38
src/kernel/memory/PageFrameAllocator.cpp
View File

@ -1,38 +0,0 @@
#include "PageFrameAllocator.h"
MemoryInfo memInfo {};
void mapMultibootMemoryMap( multiboot_info_t *mbt){
printf("mmap_addr = 0x%x, mmap_length = 0x%x\n",
(unsigned) mbt->mmap_addr, (unsigned) mbt->mmap_length);
multiboot_memory_map_t *mmap = (multiboot_memory_map_t*) mbt->mmap_addr;
for (; (unsigned long) mmap < mbt->mmap_addr + mbt->mmap_length; mmap = (multiboot_memory_map_t *) ((unsigned long) mmap + mmap->size + sizeof(mmap->size))){
if ( mmap->type == MULTIBOOT_MEMORY_AVAILABLE){
memInfo.memorySizeInBytes += mmap->len;
} else {
memInfo.reservedMemoryInBytes += mmap->len;
}
print_Multiboot_memory_Map(mmap);
}
uint32_t memorySizeInGiB = memInfo.memorySizeInBytes / 1073741824;
printf("Available Memory: 0x%x bytes, 0x%x GiB\n", memInfo.memorySizeInBytes, memorySizeInGiB );
printf("Reserved Memory: 0x%x bytes\n", memInfo.reservedMemoryInBytes );
}
void print_Multiboot_memory_Map(multiboot_memory_map_t* mmap){
printf(
"size = 0x%x, base_addr = 0x%x%08x, length = 0x%x%08x, type = 0x%x\n",
(unsigned) mmap->size,
(unsigned) (mmap->addr >> 32),
(unsigned) (mmap->addr & 0xffffffff),
(unsigned) (mmap->len >> 32),
(unsigned) (mmap->len & 0xffffffff),
(unsigned) mmap->type
);
}

20
src/kernel/memory/PageFrameAllocator.h
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@ -1,20 +0,0 @@
#pragma once
#include "../arch/i386/tty/kterm.h"
#include <stdint.h>
#include "../bootloader/multiboot.h"
struct MemoryInfo{
uint32_t memorySizeInBytes = 0;
uint32_t reservedMemoryInBytes = 0;
};
extern void *kernel_begin;
extern void *kernel_end;
void print_Multiboot_memory_Map(multiboot_memory_map_t*);
void mapMultibootMemoryMap(multiboot_info_t*);

118
src/kernel/memory/PhysicalMemoryManager.cpp
View File

@ -1,118 +0,0 @@
#include "PhysicalMemoryManager.h"
size_t mem_size = 0;
int used_blocks = 0;
size_t max_blocks = 0;
uint32_t* pmmap = 0;
size_t pmmap_size = 0;
void PhysicalMemoryManager_initialise(uint32_t physicalmemorymap_address, size_t size )
{
mem_size = size;
max_blocks = KB_TO_BLOCKS(mem_size);
used_blocks = max_blocks;
pmmap = (uint32_t*) physicalmemorymap_address;
if(max_blocks % BLOCKS_PER_WORD)
pmmap_size++;
memset(pmmap, 0xFF, pmmap_size);
}
void PhysicalMemoryManager_region_initialise(uint32_t base, size_t size)
{
size_t blocks = size /BLOCK_SIZE;
uint32_t align = base / BLOCK_SIZE;
for(size_t i = 0 ; i < blocks; i ++)
{
bitmap_unset(pmmap, align++);
used_blocks--;
}
bitmap_set(pmmap, 0);
}
void PhysicalMemoryManager_region_deinitialise(uint32_t base, size_t size )
{
size_t blocks = size / BLOCK_SIZE;
uint32_t align = base / BLOCK_SIZE;
for(size_t i = 0 ; i < blocks; i++ )
{
bitmap_set(pmmap, align++);
used_blocks++;
}
}
void PhysicalMemoryManager_initialise_available_regions(uint32_t mmap_, uint32_t mmap_end_)
{
multiboot_memory_map_t *mmap = (multiboot_memory_map_t*)mmap_;
multiboot_memory_map_t *mmap_end= (multiboot_memory_map_t*) mmap_end_;
for(int i = 0; mmap < mmap_end ; mmap++, i++)
{
if(mmap->type == MULTIBOOT_MEMORY_AVAILABLE)
{
PhysicalMemoryManager_region_initialise((uint32_t) mmap->addr, (size_t) mmap->len);
}
}
}
void PhysicalMemoryManager_deinitialise_kernel()
{
extern uint8_t kernel_begin;
extern uint8_t kernel_end;
size_t kernel_size = (size_t) &kernel_end - (size_t) &kernel_begin;
uint32_t pmmap_size_aligned = pmmap_size;
if(!IS_ALIGNED(pmmap_size_aligned, BLOCK_SIZE))
{
pmmap_size_aligned = ALIGN(pmmap_size_aligned, BLOCK_SIZE);
}
PhysicalMemoryManager_region_deinitialise((uint32_t) &kernel_begin, kernel_size);
PhysicalMemoryManager_region_deinitialise((uint32_t) &kernel_end, pmmap_size_aligned);
}
void* PhysicalMemoryManager_allocate_block()
{
if(used_blocks - max_blocks <= 0)
{
return 0;
}
int p_index = bitmap_first_unset(pmmap, p_index );
if(p_index == -1){
return 0;
}
bitmap_set(pmmap, p_index);
used_blocks++;
return (void*) (BLOCK_SIZE * p_index);
}
void PhysicalMemoryManager_free_block(void* p){
if(p==0){
return ;
}
uint32_t p_addr = (uint32_t) p;
int index = p_addr / BLOCK_SIZE;
bitmap_unset(pmmap, index);
used_blocks--;
}

34
src/kernel/memory/PhysicalMemoryManager.h
View File

@ -1,34 +0,0 @@
#pragma once
#include "../bootloader/multiboot.h"
#include <stdint.h>
#include <stddef.h>
#include "../../libc/include/mem.h"
#include "../kstructures/bitmap.h"
#define BLOCK_SIZE 4092
#define BLOCKS_PER_WORD 32
#define KB_TO_BLOCKS(x) (((x) * 1024 ) / BLOCK_SIZE)
#define IS_ALIGNED(addr, align) !((addr) & ~((align) - 1))
#define ALIGN(addr, align) (((addr) & ~((align) - 1 )) + (align))
extern void PhysicalMemoryManager_initialise(uint32_t, size_t);
extern void PhysicalMemoryManager_region_initialise(uint32_t, size_t);
extern void PhysicalMemoryManager_region_deinitialise(uint32_t,size_t);
extern void PhysicalMemoryManager_initialise_available_regions(uint32_t, uint32_t);
extern void PhysicalMemoryManager_deinitialise_kernel();
extern void* PhysicalMemoryManager_allocate_block();
extern void PhysicalMemoryManager_free_block(void* p);
extern size_t mem_size;
extern int used_blocks;
extern size_t max_blocks;
extern uint32_t* pmmap;
extern size_t pmmap_size ;

33
src/kernel/memory/SlabAllocator.h
View File

@ -1,33 +0,0 @@
#pragma once
/**
* We'll need something to this effect to allocate memory in the kernel
* this will hopefully someday implement a full slab allocator
**/
enum SlabState {
empty,
partial,
full
};
class CacheSlab {
const int SlabSize = 4000;
void* start = 0x0;
};
class Allocator {
public:
Allocator();
~Allocator();
void* kmalloc( int size );
void kfree (void* address);
private:
CacheSlab** _cache;
};

142
src/kernel/memory/memory.cpp Normal file
View File

@ -0,0 +1,142 @@
#include "./memory.h"
uint32_t* memoryBitMap;
/*
*/
void PhysicalMemory::setup( MemoryInfo* memory) {
// calculate the maximum number of blocks
max_blocks = KB_TO_BLOCKS(memory->TotalMemory);
used_blocks = 0;
memoryBitMap = (uint32_t*) 0x00a00000;
printf("Maximum Number of blocks: 0x%x, Number of bytes for memMap: 0x%x\n", max_blocks , (max_blocks/8));
//Size of memory map
uint32_t memMap_size = (max_blocks / 8 ) ;
printf("Memory Map size: 0x%x\n", memMap_size );
printf("size of int in bytes: 0x%x \n" , sizeof(int));
// Set all places in memory as free
memset(memoryBitMap, 0xFF, memMap_size );
}
// NOTE: this can only give blocks of 4kb at a time!
void* PhysicalMemory::allocate_block() {
uint8_t blocks_available = max_blocks - used_blocks;
// Are there any blocks available?
if( blocks_available <= 0)
{
printf("No blocks available. Blocks Delta: 0x%x\n", blocks_available);
return 0;
}
// Find 1 free block somewhere
int free_block_index = bitmap_first_unset(memoryBitMap, (max_blocks /8) /*memMap Size*/ );
if(free_block_index == -1)
{
printf("Could not find a good block!\n");
// Could not find a block
return (void*)0xFFFF;
}
if(free_block_index == 0)
printf("Somethings wrong!!!\n");
// Set the block to be used!
bitmap_unset(memoryBitMap, free_block_index);
// Increase the used_block count!
used_blocks++;
printf("used blocks: 0x%x\n", used_blocks);
// return the pointer to the physical address
return (void*) (BLOCK_SIZE * free_block_index);
}
void PhysicalMemory::free_block(void* p) {
// If it is a null pointer we don't need to do anything.
if(p==0) {
return;
}
// calculate the index into the bitmap
int index = ((uint32_t) p) / BLOCK_SIZE;
// set the block to be free
bitmap_set(memoryBitMap, index);
used_blocks--;
printf("used blocks: 0x%x, after free\n", used_blocks);
}
void PhysicalMemory::allocate_region(uint32_t startAddress, uint32_t size) {
// every bit should be 4KiB
// every byte is 8*4KiB = 32KiB
int NumberOfBlocksToAllocate = ( size / 1024) / 4 / 8 + 1;
int startBlock = (startAddress / 1024) / 4 / 8 ;
// printf("NumberOfBlocksToAllocate: 0x%x\n", NumberOfBlocksToAllocate);
//printf( "start block: 0x%x\n" , startBlock);
for( int i = 0; i < NumberOfBlocksToAllocate; i++)
{
//printf("ALLOCATE BLOCK: 0x%x\n" , startBlock + i );
bitmap_unset(memoryBitMap, startBlock+ i);
used_blocks++;
}
}
void PhysicalMemory::deallocate_region(uint32_t StartAddress , uint32_t size ) {
// NOT IMPLEMENTED YET
}
void mapMultibootMemoryMap( MemoryInfo* memInfo , multiboot_info_t *mbt) {
printf("mmap_addr = 0x%x, mmap_length = 0x%x\n",
(unsigned) mbt->mmap_addr, (unsigned) mbt->mmap_length);
multiboot_memory_map_t *mmap = (multiboot_memory_map_t*) mbt->mmap_addr;
for (; (unsigned long) mmap < mbt->mmap_addr + mbt->mmap_length; mmap = (multiboot_memory_map_t *) ((unsigned long) mmap + mmap->size + sizeof(mmap->size))){
if ( mmap->type == MULTIBOOT_MEMORY_AVAILABLE){
memInfo->TotalMemory += mmap->len;
} else {
memInfo->ReservedMemory += mmap->len;
}
print_Multiboot_memory_Map(mmap);
}
}
/**
* @brief Debug Verbose functions
*
* @param mmap
*/
void print_Multiboot_memory_Map(multiboot_memory_map_t* mmap) {
printf(
"size = 0x%x, base_addr = 0x%x%08x, length = 0x%x%08x, type = 0x%x\n",
(unsigned) mmap->size,
(unsigned) (mmap->addr >> 32),
(unsigned) (mmap->addr & 0xffffffff),
(unsigned) (mmap->len >> 32),
(unsigned) (mmap->len & 0xffffffff),
(unsigned) mmap->type
);
}

48
src/kernel/memory/memory.h Normal file
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@ -0,0 +1,48 @@
#pragma once
#include <stdint.h>
#include <stddef.h>
#include "memoryinfo.h"
#include "../bootloader/multiboot.h"
#include "../tty/kterm.h"
#include "../../libc/include/mem.h"
#include "../kstructures/bitmap.h"
#define BLOCK_SIZE 4092
#define BLOCKS_PER_WORD 32 // A word is 16 bit in x86 machines according to my google search results!
#define KB_TO_BLOCKS(x) (x / BLOCK_SIZE)
#define IS_ALIGNED(addr, align) !((addr) & ~((align) - 1))
#define ALIGN(addr, align) (((addr) & ~((align) - 1 )) + (align))
extern uint32_t kernel_begin;
extern uint32_t kernel_end;
void initialise_available_regions(uint32_t memoryMapAddr, uint32_t memoryMapLastAddr, uint32_t* memoryBitMap, int* used_blocks);
extern uint32_t* memoryBitMap;
class PhysicalMemory
{
public:
void setup(MemoryInfo* memory);
void destroy();
void free_block(void* ptr);
void* allocate_block();
void allocate_region(uint32_t, uint32_t);
void deallocate_region(uint32_t , uint32_t );
private:
size_t pmmap_size;
size_t max_blocks;
int used_blocks;
};
void mapMultibootMemoryMap( MemoryInfo* memInfo , multiboot_info_t *mbt);
/**
* @brief Debug Verbose Functions
*
* @param mmap
*/
void print_Multiboot_memory_Map(multiboot_memory_map_t* mmap);

20
src/kernel/memory/memoryinfo.h Normal file
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@ -0,0 +1,20 @@
#pragma once
#include <stdint.h>
#include <stddef.h>
struct MemoryArea{
void* StartAddress;
size_t Size;
unsigned int type;
MemoryArea* Next;
}__attribute__((packed));
struct MemoryInfo {
uint32_t TotalMemory;
uint32_t ReservedMemory;
MemoryArea* MemoryRegionList;
}__attribute__((packed));

13
src/kernel/sv-terminal/superVisorTerminal.cpp
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@ -1,6 +1,6 @@
#include "superVisorTerminal.h"
void startSuperVisorTerminal(){
void startSuperVisorTerminal(BootInfo* bootinfo){
while (true){
printf("SUPERVISOR:>$ " );
@ -40,7 +40,16 @@ void startSuperVisorTerminal(){
printf("========= Memory ==========\n");
printf("Kernel MemoryMap:\n");
printf("kernel: 0x%x - 0x%x\n", &kernel_begin , &kernel_end);
printf("Frames used: 0x%x blocks of 4 KiB\n", used_blocks);
printf("Frames used: 0x%x blocks of 4 KiB\n", 0);
const int bytesInGiB = 1073741824;
int64_t bytesLeft = (bootinfo->memory->TotalMemory % bytesInGiB) / bytesInGiB;
int64_t effectiveNumberOfGib = bootinfo->memory->TotalMemory / bytesInGiB;
int64_t GiBs = effectiveNumberOfGib + bytesLeft;
printf("Available Memory: %d bytes, %d GiB\n", bootinfo->memory->TotalMemory, GiBs );
printf("Reserved Memory: %d bytes\n", bootinfo->memory->ReservedMemory);
//printf("\n\n");
//PrintPhysicalMemoryAllocation( );

5
src/kernel/sv-terminal/superVisorTerminal.h
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@ -3,6 +3,7 @@
#include "../time.h"
#include "../pit.h"
#include "../keyboard/keyboard.h"
#include "../memory/physical/PhysicalMemoryManager.h"
#include "../memory/memory.h"
#include "../bootinfo.h"
void startSuperVisorTerminal();
void startSuperVisorTerminal(BootInfo * );

4
src/libc/include/mem.h
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@ -1,8 +1,8 @@
inline void* memset (void* ptr, int value, size_t num){
for( int i = 0; i < num; i++ )
{
int* data = (int*)ptr+ i;
*data = value;
unsigned char* data = (unsigned char*)ptr+ i;
*data = (unsigned char)value;
}
return ptr;
}

21
todo.md
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@ -0,0 +1,21 @@
# TODO list
![Todo image](https://camo.githubusercontent.com/c43d969d9d071c8342e9a69cdd6acb433c541f431127738974ce22290c46f2b8/68747470733a2f2f692e696d6775722e636f6d2f4f764d5a4273392e6a7067)
This list keeps me focused and organised so I don't forget what
needs to be done. It is a expansion on the features markdown file which describes the features. Here I put things I need to remember
to do on a more in depth level.
## --
[ ] Setup paging \
[ ] HELP command
[ ] Setup a proper HEAP \
[ ] Setup a proper Stack \
[ ] Setup KMalloc and KFree \
[ ] Merge Functioning Feature branches into sandboxKernelDev \
[ ] Remove merged feature branches \
[ ] Merge sandboxKernelDev with dev \
[ ] Remove sandboxKernelDev branch \
[ ] Implement proper virtual filesystem