Couple of small changes

* Commented out the map page function call to handle page not present
* Mapped the ACPI_RECLAIMABLE_MEMORY
* Set VBE to false when VBE is not initialized by the bootloader

.gdbinit

@@ -0,0 +1,7 @@
+target remote localhost:1234
+
+file root/boot/myos.bin
+symbol-file kernel.sym
+
+break prekernel/prekernel.cpp:18
+continue

.gitignore

@@ -1,8 +1,15 @@
-build
-CON
-.vscode
+build/
+bin/
+.vscode/
+.idea/
 isodir/
 root/
 *.iso
 *.img
+*.sym
+*.o
+*.a
 
+
+/CoreLib/warnings.log
+/kernel/warnings.log

CoreLib/List.h

@@ -0,0 +1,12 @@
+//
+// Created by nigel on 25/02/23.
+//
+#pragma once
+
+
+class List {
+public:
+    List* next;
+    void* data;
+};
+

CoreLib/Makefile

@@ -0,0 +1,35 @@
+CPP = /opt/cross/bin/i686-elf-g++
+CFLAGS = -ffreestanding -Og -ggdb -Wall -Wextra
+
+BUILD_DIR = ../build/CoreLib
+OBJ_FOLDER = ../bin/CoreLib
+OUTPUTFILE = $(BUILD_DIR)/libCoreLib.a
+
+OFILES = $(OBJ_FOLDER)/ctype.o $(OBJ_FOLDER)/memory.o $(OBJ_FOLDER)/path.o $(OBJ_FOLDER)/stack.o $(OBJ_FOLDER)/string.o $(OBJ_FOLDER)/stringview.o
+
+.phony: all
+all: $(OUTPUTFILE)
+	cp *.h $(BUILD_DIR)/include/CoreLib
+
+$(OUTPUTFILE): $(OFILES)
+	pwd
+	ar -rc $(OUTPUTFILE) $(OFILES)
+
+$(OBJ_FOLDER)/ctype.o: ctype.cpp
+	$(CPP) -c ctype.cpp -o $(OBJ_FOLDER)/ctype.o $(CFLAGS)
+
+$(OBJ_FOLDER)/memory.o: Memory.cpp
+	$(CPP) -c Memory.cpp -o $(OBJ_FOLDER)/memory.o $(CFLAGS)
+
+$(OBJ_FOLDER)/path.o: Path.cpp
+	$(CPP) -c Path.cpp  -o $(OBJ_FOLDER)/path.o $(CFLAGS)
+
+$(OBJ_FOLDER)/stack.o: Stack.cpp
+	$(CPP) -c Stack.cpp  -o $(OBJ_FOLDER)/stack.o $(CFLAGS)
+
+$(OBJ_FOLDER)/string.o: String.cpp
+	$(CPP) -c String.cpp -o $(OBJ_FOLDER)/string.o $(CFLAGS)
+
+$(OBJ_FOLDER)/stringview.o: StringView.cpp
+	$(CPP) -c StringView.cpp  -o $(OBJ_FOLDER)/stringview.o $(CFLAGS)
+

CoreLib/Memory.cpp

@@ -0,0 +1,107 @@
+//
+// Created by nigel on 19/02/23.
+//
+#include "Memory.h"
+
+void* memset (void* ptr, int value, size_t num)
+{
+    for( int i = 0; i < num; i++ )
+    {
+        unsigned char* data  = (unsigned char*)ptr+ i;
+        *data = (unsigned char)value;
+    }
+    return ptr;
+}
+
+
+int memcmp( const void* ptr1, const void* ptr2, size_t num)
+{
+    auto* cs = (const unsigned char*) ptr1;
+    auto* ct = (const unsigned char*) ptr2;
+
+
+    for (int i = 0 ; i < num ; i++, cs++, ct++ ){
+        if( *cs != *ct)
+            return *cs - *ct;
+
+    }
+
+    return 0;
+
+}
+
+[[maybe_unused]] void memcpy (void* dest, const void* src, size_t count ){
+    for( int i = 0; i < count; i++){
+        ((char *)dest)[i] = ((const char*)src)[i];
+    }
+}
+
+
+
+
+
+
+size_t strlen(const char* str) {
+    size_t len = 0;
+    while(str[len]){
+        len++;
+    }
+    return len;
+}
+
+int strncmp ( const char* str1, const char* str2, size_t num ){
+    for( int i = 0; i < num ; i++){
+
+        if( str1[i] < str2[i]){
+            return -1;
+        }
+
+        if( str1[i] > str2[i] ){
+            return 1;
+        }
+
+
+    }
+
+    return 0;
+}
+
+char* strchr(const char* s , int c){
+    while(*s) {
+        if(*s == c) return const_cast<char*>(s);
+        s++;
+    }
+    return NULL;
+}
+char* strtok(char* str, const char* delim , char**saveptr){
+    char *begin;
+    if(str) {
+        begin = str;
+    }
+    else if (*saveptr) {
+        begin = *saveptr;
+    }
+    else {
+        return NULL;
+    }
+
+    while(strchr(delim, begin[0])) {
+        begin++;
+    }
+
+
+    char *next = NULL;
+    for(int i = 0; i < strlen(delim); i++) {
+        char *temp = strchr(begin, delim[i]);
+        if(temp < next || next == NULL) {
+            next = temp;
+        }
+    }
+    if(!next) {
+        *saveptr = NULL;
+        return begin;
+    }
+    *next = 0;
+    *saveptr=next+1;
+    return begin;
+}

CoreLib/Memory.h

@@ -0,0 +1,16 @@
+#pragma once
+
+#include <stddef.h>
+#include <stdint.h>
+
+void* memset (void* ptr, int value, size_t num);
+
+int memcmp( const void* ptr1, const void* ptr2, size_t num);
+
+[[maybe_unused]] void memcpy (void* dest, const void* src, size_t count );
+
+size_t strlen(const char* str);
+
+int strncmp ( const char* str1, const char* str2, size_t num );
+
+char* strtok(char* str, const char* delim , char**saveptr);

CoreLib/Path.cpp

@@ -0,0 +1,24 @@
+//
+// Created by nigel on 19/02/23.
+//
+#include "Path.h"
+
+Path::Path(String path)
+: path(path)
+{
+
+}
+
+StringView Path::getbasename()
+{
+    unsigned int path_length = path.length();
+    int i = path_length;
+    while (path[i] != '/')
+        i--;
+
+    return {path,static_cast<unsigned int>(i +1), path_length};
+}
+
+char* Path::str() {
+    return path.str();
+}

CoreLib/Path.h

@@ -0,0 +1,22 @@
+//
+// Created by nigel on 19/02/23.
+//
+#pragma once
+#include <stddef.h>
+#include "StringView.h"
+
+
+class Path{
+public:
+    explicit Path(String path);
+
+    StringView getbasename();
+
+    char* str();
+
+private:
+    String path;
+
+};
+
+

CoreLib/Stack.cpp

@@ -0,0 +1,3 @@
+//
+// Created by nigel on 19/02/23.
+//

CoreLib/Stack.h

@@ -0,0 +1,73 @@
+#pragma once
+#include "../kernel/memory/KernelHeap.h"
+#include <stdint.h>
+
+template <typename T>
+class Stack {
+    public:
+        inline Stack() {
+                elements = (T[MAX_STACK_SIZE]) malloc(MAX_STACK_SIZE * sizeof(T));
+                num = 0;
+
+        }
+
+        inline void  Push(T element){
+            num++;
+            if(num > MAX_STACK_SIZE)
+                grow();
+
+            element[num] = element;
+        }
+
+     
+        inline T Pop()
+        {
+            T temp = elements[num];
+            num --;
+
+            return temp;
+        }
+
+        inline bool isEmpty()
+        {
+            return num == 0;
+        }
+
+        inline bool isFull()
+        {
+                return num == MAX_STACK_SIZE;
+        }
+
+      
+        inline int count()
+        {
+                return num;
+        }
+
+        inline ~Stack()
+        {
+            free(elements);
+        }
+
+
+    private:
+        unsigned int MAX_STACK_SIZE;
+        T[MAX_STACK_SIZE] elements;
+        unsigned int num;
+
+        inline void grow (){
+            MAX_STACK_SIZE = MAX_STACK_SIZE + (int)(MAX_STACK_SIZE / 4);
+            T[] new_elements =(T[MAX_STACK_SIZE]) malloc(MAX_STACK_SIZE * sizeof(T));
+
+            for ( int i = 0; i < num ; i++){
+                new_elements[i] = elements[i];
+            }
+            free(elements);
+            elements = new_elements;
+
+        }
+
+
+
+};
+

CoreLib/String.cpp

@@ -0,0 +1,39 @@
+#include "String.h"
+#include <stdint.h>
+#include <stddef.h>
+
+
+String::String(char* characters)
+: chars(characters)
+        {
+
+        }
+
+char* String::str(){
+    return chars;
+}
+
+unsigned int String::length ()
+{
+    int i = 0;
+
+    while (  chars[i] != '\0'){
+        i++;
+    }
+
+    return i;
+}
+
+// Returns a null character if size exceeds limits
+char String::operator[] (size_t idx)
+{
+    if( idx  > this->length())
+        return '\0';
+
+    return chars[idx];
+}
+
+const char String::operator[](size_t idx) const {
+return (const char) chars[idx];
+}
+

CoreLib/String.h

@@ -0,0 +1,18 @@
+#pragma once
+#include <stddef.h>
+
+class  String {
+public:
+    String(char* characters);
+    String(String&) = default;
+    unsigned int length();
+
+    char* str ();
+    char operator[](size_t index) ;
+    const char operator[](size_t idx) const;
+
+protected:
+    char* chars;
+
+
+};

CoreLib/StringView.cpp

@@ -0,0 +1,14 @@
+//
+// Created by nigel on 19/02/23.
+//
+#include "StringView.h"
+
+StringView::StringView(String string, unsigned int start, unsigned int end)
+        : String(string), begin(start), end(end)
+{
+
+}
+
+char* StringView::str(){
+   //TODO: Not implemented
+}

CoreLib/StringView.h

@@ -0,0 +1,14 @@
+//
+// Created by nigel on 19/02/23.
+//
+#pragma once
+#include "String.h"
+
+class StringView : String {
+public:
+    StringView(String string, unsigned int start, unsigned  int end );
+    char* str ();
+private:
+    unsigned int begin;
+    unsigned int end;
+};

CoreLib/ctype.cpp

@@ -0,0 +1,141 @@
+//
+// Created by nigel on 25/02/23.
+//
+#include "ctype.h"
+
+int isupper (int ch){
+    if( ch >= 'A' && ch <= 'Z'){
+        return 1;
+    }
+    return 0;
+}
+int islower (int ch){
+    if(ch >= 'a' && ch <= 'z'){
+        return 1;
+    }
+    return 0;
+}
+
+int isalpha (int ch) {
+    if(isupper(ch)){
+        return 1;
+    }
+    if(islower(ch)){
+        return 1;
+    }
+    return 0;
+}
+int isdigit (int ch){
+    if(ch >= '0' && ch <= '9'){
+        return 1;
+    }
+    return 0;
+}
+
+int isxdigit (int ch){
+    if(isdigit(ch)){
+        return 1;
+    }
+
+    if( ch >= 'a' && ch <= 'f'){
+        return 1;
+    }
+
+    if( ch >= 'A' && ch <= 'F'){
+        return 1;
+    }
+    return 0;
+}
+
+int iscntrl (int ch){
+    if(ch >= 0x00 && ch <= 0x1f )
+        return 1;
+    if(ch == 0x7f)
+        return 1;
+    return 0;
+}
+
+
+int isgraph (int ch){
+    if(isdigit(ch))
+        return 1;
+    if(isupper(ch))
+        return 1;
+    if(islower(ch))
+        return 1;
+    if(ispunct(ch))
+        return 1;
+    return 0;
+}
+
+int isspace(int ch){
+    if (ch == 0x20)
+        return 1;
+    if(ch == 0x0c)
+        return 1;
+    if(ch == 0x0a)
+        return 1;
+    if(ch == 0x0d)
+        return 1;
+    if(ch == 0x09)
+        return 1;
+    if(ch == 0x0b)
+        return 1;
+
+    return 0;
+}
+
+int isblank (int ch){
+    if( ch == 0x20 || ch == 0x09)
+        return 1;
+    return 0;
+}
+
+int ispunct(int ch){
+    if(ch >= '!' && ch <= '~')
+        return 1;
+    return 0;
+}
+
+int isprint (int ch){
+    if (isdigit(ch))
+        return 1;
+    if(isupper(ch))
+        return 1;
+    if(islower(ch))
+        return 1;
+    if(ispunct(ch))
+        return 1;
+    if(isspace(ch))
+        return 1;
+    return 0;
+}
+
+
+int tolower(int ch){
+
+    if(islower(ch)) return ch;
+    int diff = 'a' - 'A';
+    return ch + diff;
+}
+
+int toupper(int ch){
+    if(isupper(ch)) return ch;
+    int diff = 'a' - 'A';
+    return ch - diff;
+}
+
+
+
+int isalnum (int ch){
+    if(isdigit(ch)){
+        return 1;
+    }
+
+   if(isalpha(ch)){
+       return 1;
+   }
+
+    return 0;
+
+}

CoreLib/ctype.h

@@ -0,0 +1,21 @@
+//
+// Created by nigel on 25/02/23.
+//
+#pragma once
+
+//NOTE: Uses default locale
+int isupper (int ch);
+int islower (int ch);
+int isalpha (int ch);
+int isdigit (int ch);
+int isxdigit (int ch);
+int iscntrl (int ch);
+int isgraph(int ch);
+int isspace(int ch);
+int isblank(int ch);
+int ispunct(int ch);
+int isprint(int ch);
+int isalnum (int ch);
+int tolower(int ch);
+int toupper(int ch);
+

Makefile

@@ -1,114 +0,0 @@
-
-EMULATOR = qemu-system-i386
-AS = ${HOME}/opt/cross/bin/i686-elf-as
-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 \
-$(BUILD_DIR)/PhysicalMemoryManager.o \
-$(BUILD_DIR)/io.o \
-$(BUILD_DIR)/PageDirectory.o \
-$(BUILD_DIR)/gdtc.o \
-$(BUILD_DIR)/idt.o \
-$(BUILD_DIR)/pci.o \
-$(BUILD_DIR)/pic.o \
-$(BUILD_DIR)/string.o \
-$(BUILD_DIR)/pcidevice.o \
-$(BUILD_DIR)/atapiDevice.o 
-
-
-
-SRC_DIR = src
-BUILD_DIR = build
-
-CRTBEGIN_OBJ = $(shell $(CC) $(CFLAGS) -print-file-name=crtbegin.o)
-CRTEND_OBJ = $(shell $(CC) $(CFLAGS) -print-file-name=crtend.o)
-
-CRTI_OBJ = $(BUILD_DIR)/crti.o
-CRTN_OBJ = $(BUILD_DIR)/crtn.o
-OBJ_LINK_LIST = $(CRTI_OBJ) $(CRTBEGIN_OBJ) $(OFILES) $(CRTEND_OBJ) $(CRTN_OBJ)  
-INTERNAL_OBJS = $(CRTI_OBJ) $(OFILES) $(CRTN_OBJ)
-
-
-all: clean build 
-
-build: build_kernel iso
-
-
-
-clean_iso: 
-	if [[ -a isodir/boot ]] ; then rm root/boot -rd ; fi
-	if [ -f build/barinkOS.iso ] ; then rm build/barinkOS.iso ; fi
-	
-iso: clean_iso clean build
-	mkdir -p root/boot/grub
-	cp build/myos.bin root/boot/myos.bin
-	cp src/grub.cfg root/boot/grub/grub.cfg
-	grub-mkrescue -o build/barinkOS.iso root
-	
-test:
-	$(EMULATOR)  -kernel $(BUILD_DIR)/myos.bin -serial stdio -vga std -display gtk -m 2G -cpu core2duo 
-
-test_iso: 
-	$(EMULATOR)  -cdrom $(BUILD_DIR)/barinkOS.iso -serial stdio -vga std -display gtk -m 2G -cpu core2duo 
-
-build_kernel: $(OBJ_LINK_LIST)
-	$(CC) -T $(SRC_DIR)/kernel//linker.ld -o $(BUILD_DIR)/myos.bin \
-	 -ffreestanding -O2 -nostdlib $(OBJ_LINK_LIST) -lgcc
-
-build_x86_64: 
-	$(AS) $(SRC_DIR)/cgc/x86_64/crti.s -o $(BUILD_DIR)/crti_64.o
-	$(AS) $(SRC_DIR)/cgc/x86_64/crtn.s -o $(BUILD_DIR)/crtn.o
-
-clean: 
-	rm -f $(BUILD_DIR)/myos.bin $(INTERNAL_OBJS)
-
-$(BUILD_DIR)/kernel.o:
-	$(CPP) -c $(SRC_DIR)/kernel/kernel.cpp -o $(BUILD_DIR)/kernel.o $(CFLAGS) -fno-exceptions -fno-rtti
-
-$(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 $(BUILD_DIR)/boot.o
-
-$(BUILD_DIR)/crti.o:
-	$(AS) $(SRC_DIR)/kernel/crti.s -o $(BUILD_DIR)/crti.o
-
-$(BUILD_DIR)/crtn.o:
-	$(AS) $(SRC_DIR)/kernel/crtn.s -o $(BUILD_DIR)/crtn.o
-
-$(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 $(CFLAGS) -fno-exceptions -fno-rtti
-
-$(BUILD_DIR)/gdtc.o:
-	$(CPP) -c $(SRC_DIR)/kernel/gdt/gdtc.cpp -o $(BUILD_DIR)/gdtc.o $(CFLAGS) -fno-exceptions -fno-rtti
-
-
-$(BUILD_DIR)/pic.o:
-	$(CPP) -c $(SRC_DIR)/kernel/pic/pic.cpp -o $(BUILD_DIR)/pic.o $(CFLAGS) -fno-exceptions -fno-rtti
-
-$(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)/pci.o:
-	$(CPP) -c $(SRC_DIR)/kernel/pci.cpp  -o $(BUILD_DIR)/pci.o $(CFLAGS) -fno-exceptions -fno-rtti
-
-$(BUILD_DIR)/pcidevice.o:
-	$(CPP) -c $(SRC_DIR)/kernel/pci/pciDevice.cpp  -o $(BUILD_DIR)/pcidevice.o $(CFLAGS) -fno-exceptions -fno-rtti
-
-$(BUILD_DIR)/atapiDevice.o:
-	$(CPP) -c $(SRC_DIR)/kernel/drivers/atapi/atapiDevice.cpp  -o $(BUILD_DIR)/atapiDevice.o $(CFLAGS) -fno-exceptions -fno-rtti

README.md

@@ -17,16 +17,23 @@ W.I.P - Working on interrupt handling
 ![Multiboot integration](screenshots/multiboot.png) \
 Multiboot information can be read by the kernel.
 
+![Page faulting](screenshots/PageFault.png) \
+Enabled paging and am getting page faults!
+
 ![PCI enumeration](screenshots/PCIBusEnumeration.png) \
 Enumerating the PCI bus 
 
 ![ATAPI CD-ROM Identification](screenshots/CD-ROM_Identify.png) \
 Correctly identified our ATAPI device 🎉
 
+![Reading Files from FAT-16](screenshots/ReadingFilesFromFAT16.png) \
+Reading a FILE from a FAT-16 Formatted drive 
+
 ________________________
 
 ### 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

features.md

@@ -1,29 +1,37 @@
 # TODO list 
-## Start planning
-<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) \
+## Basics
+
+<label>
+<input type="checkbox"  checked/>
+</label> 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 \
+<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/> Enable CMOS clock \
+<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" /> 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" checked/> PCI support \
-<input type="checkbox" /> ATA PIO Mode 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" checked/>  Paging \
+<input type="checkbox" checked/> Virtual memory management \
+<input type="checkbox" checked/> The heap: allocating memory at runtime (malloc and free) is almost impossible to go without. \
+<input type="checkbox" /> Enable SIMD Extensions (SSE)
+<input type="checkbox" checked/> PCI support \
+<input type="checkbox" checked/> 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 +40,11 @@
 <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 \
+
 <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 \
+<input type="checkbox" /> FAT16 Filesystem \

kernel/Makefile

@@ -0,0 +1,132 @@
+AS = /opt/cross/bin/i686-elf-as
+CC = /opt/cross/bin/i686-elf-gcc
+CPP = /opt/cross/bin/i686-elf-g++
+CFLAGS =  -ffreestanding -Og -ggdb  -Wall -Wextra  -I ../build/CoreLib/include
+BUILD_DIR = ../build/kernel
+OBJ_DIR = ../bin/kernel
+
+CRTBEGIN_OBJ = $(shell $(CC) $(CFLAGS) -print-file-name=crtbegin.o)
+CRTEND_OBJ = $(shell $(CC) $(CFLAGS) -print-file-name=crtend.o)
+
+CRTI_OBJ = $(OBJ_DIR)/crti.o
+CRTN_OBJ = $(OBJ_DIR)/crtn.o
+
+OFILES = $(OBJ_DIR)/boot.o	\
+ 		 $(OBJ_DIR)/kterm.o \
+ 		 $(OBJ_DIR)/kernel.o \
+ 		 $(OBJ_DIR)/memory.o \
+ 		 $(OBJ_DIR)/paging.o \
+ 		 $(OBJ_DIR)/VFS.o \
+ 		 $(OBJ_DIR)/pit.o \
+ 		 $(OBJ_DIR)/time.o \
+ 		 $(OBJ_DIR)/keyboard.o \
+ 		 $(OBJ_DIR)/io.o \
+ 		 $(OBJ_DIR)/processor.o \
+		 $(OBJ_DIR)/gdtc.o \
+		 $(OBJ_DIR)/idt.o \
+		 $(OBJ_DIR)/pic.o \
+		 $(OBJ_DIR)/sv-terminal.o \
+		 $(OBJ_DIR)/prekernel.o \
+		 $(OBJ_DIR)/KHeap.o \
+		 $(OBJ_DIR)/pci.o \
+		 $(OBJ_DIR)/pcidevice.o \
+		 $(OBJ_DIR)/atapiDevice.o \
+		 $(OBJ_DIR)/ataDevice.o \
+		 $(OBJ_DIR)/rsdp.o \
+		 $(OBJ_DIR)/acpi.o \
+		 $(OBJ_DIR)/fat.o
+
+OBJ_LINK_LIST = $(CRTI_OBJ) $(CRTBEGIN_OBJ) $(OFILES) $(CRTEND_OBJ) $(CRTN_OBJ)  
+INTERNAL_OBJS = $(CRTI_OBJ) $(OFILES) $(CRTN_OBJ)
+
+all: clean build
+
+clean:
+	rm $(OBJ_DIR)/* -r
+
+
+build: $(OBJ_LINK_LIST)
+	$(CPP) -T linker.ld -o $(BUILD_DIR)/myos.bin -ffreestanding -ggdb -Og -nostdlib $(OBJ_LINK_LIST) -lgcc -L ../build/CoreLib -lCoreLib
+
+# C++ definition -> Object files
+$(OBJ_DIR)/kernel.o: kernel.cpp
+	$(CPP) -c kernel.cpp -o $(OBJ_DIR)/kernel.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/kterm.o:
+	$(CPP) -c terminal/kterm.cpp  -o $(OBJ_DIR)/kterm.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/io.o:
+	$(CPP) -c io/io.cpp  -o $(OBJ_DIR)/io.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/idt.o:
+	$(CPP) -c interrupts/idt.cpp -o $(OBJ_DIR)/idt.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/gdtc.o:
+	$(CPP) -c memory/gdt/gdtc.cpp -o $(OBJ_DIR)/gdtc.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/pic.o:
+	$(CPP) -c drivers/pic/pic.cpp -o $(OBJ_DIR)/pic.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/PhysicalMemoryManager.o:
+	$(CPP) -c memory/PhysicalMemoryManager.cpp  -o $(OBJ_DIR)/PhysicalMemoryManager.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/pci.o:
+	$(CPP) -c pci/pci.cpp  -o $(OBJ_DIR)/pci.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/pcidevice.o:
+	$(CPP) -c pci/pciDevice.cpp  -o $(OBJ_DIR)/pcidevice.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/atapiDevice.o:
+	$(CPP) -c storage/atapi/atapiDevice.cpp  -o $(OBJ_DIR)/atapiDevice.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/ataDevice.o:
+	$(CPP) -c "storage/ata pio/ATAPIO.cpp"  -o $(OBJ_DIR)/ataDevice.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/rsdp.o:
+	$(CPP) -c acpi/rsdp.cpp  -o $(OBJ_DIR)/rsdp.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/acpi.o:
+	$(CPP) -c acpi/acpi.cpp -o $(OBJ_DIR)/acpi.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/pit.o:
+	$(CPP) -c drivers/pit/pit.cpp  -o $(OBJ_DIR)/pit.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/VFS.o:
+	$(CPP) -c storage/vfs/vfs.cpp  -o $(OBJ_DIR)/VFS.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/keyboard.o:
+	$(CPP) -c drivers/ps-2/keyboard.cpp  -o $(OBJ_DIR)/keyboard.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/time.o:
+	$(CPP) -c time.cpp  -o $(OBJ_DIR)/time.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/sv-terminal.o:
+	$(CPP) -c supervisorterminal/superVisorTerminal.cpp  -o $(OBJ_DIR)/sv-terminal.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/memory.o:
+	$(CPP) -c memory/PhysicalMemoryManager.cpp  -o $(OBJ_DIR)/memory.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/paging.o:
+	$(CPP) -c memory/VirtualMemoryManager.cpp -o $(OBJ_DIR)/paging.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/KHeap.o:
+	$(CPP) -c memory/KernelHeap.cpp -o $(OBJ_DIR)/KHeap.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/prekernel.o:
+	$(CPP) -c prekernel/prekernel.cpp -o $(OBJ_DIR)/prekernel.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/processor.o:
+	$(CPP) -c i386/processor.cpp -o $(OBJ_DIR)/processor.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+$(OBJ_DIR)/fat.o:
+	$(CPP) -c storage/filesystems/FAT/FAT.cpp -o $(OBJ_DIR)/fat.o $(CFLAGS) -fno-exceptions -fno-rtti
+
+# Assembly -> Object files
+$(OBJ_DIR)/boot.o:
+	$(AS) boot/boot.s -o $(OBJ_DIR)/boot.o
+
+$(OBJ_DIR)/crti.o:
+	$(AS) crti.s -o $(OBJ_DIR)/crti.o
+
+$(OBJ_DIR)/crtn.o:
+	$(AS) crtn.s -o $(OBJ_DIR)/crtn.o

kernel/acpi/acpi.cpp

@@ -0,0 +1,76 @@
+#include "acpi.h"
+#include "../../CoreLib/Memory.h"
+#include "../memory/VirtualMemoryManager.h"
+
+RSDPDescriptor* ACPI::rsd_ptr;
+RSCPDescriptor20* ACPI::rsd2_ptr;
+RSDT* ACPI::rsd_table;
+
+const int KERNEL_OFFSET = 0xC0000000;
+
+void ACPI::initialize(){
+    // Find the Root System Description Pointer
+    ACPI::rsd_ptr = FindRSD();
+    printf("RSD address: 0x%x\n", ACPI::rsd_ptr);
+    printRSD(rsd_ptr);
+
+
+    if( rsd_ptr->Revision == 0 ){
+        // Using version 1.0 of the ACPI specification
+        int sum = rsd_ptr->Checksum;
+        for (int i =0; i < sizeof(RSDPDescriptor) ; i++) {
+            sum += ((char*)rsd_ptr)[i];
+        }
+
+        printf(" 0x%x sum\n", sum);
+        if(sum & 0xfff0)
+            printf("valid rsd!\n");
+        else
+            printf("invalid rsd\n");
+
+        printf("rsdp: 0x%x\n", rsd_ptr);
+
+        printf("0x%x address\n", (rsd_ptr->RsdtAddress));
+        Immediate_Map(rsd_ptr->RsdtAddress + KERNEL_OFFSET, rsd_ptr->RsdtAddress);
+
+        RSDT* rootSystemDescriptionTable = (RSDT*)(rsd_ptr->RsdtAddress + KERNEL_OFFSET);
+        //printf("0x%x Root System Descriptor address\n", rootSystemDescriptionTable);
+        // checksum it, but we'll ignore it for now
+        printf("signature ");
+        for (int i = 0; i < 4; i++) {
+            kterm_put( rootSystemDescriptionTable->h.Signature[i]);
+        }
+        kterm_put('\n');
+
+
+        int entries = (rootSystemDescriptionTable->h.Length - sizeof (rootSystemDescriptionTable->h)) /4;
+        printf("%d num entries\n", entries);
+        for( int i = 0; i < entries; i++){
+            ACPISDTHeader* h = (ACPISDTHeader*) rootSystemDescriptionTable->PointerToSDT + i ;
+            if(strncmp(h->Signature, "FACP", 4)){
+                printf("Found FACP Entry!\n");
+            }
+        }
+
+
+    } else{
+        // parse it as of version2.0
+        printf("rsd2_ptr\n");
+        ACPI::rsd2_ptr = (RSCPDescriptor20*)rsd_ptr;
+    }
+
+
+
+/*
+    auto tableHeader = &rootSystemDescriptionTable->h;
+
+    // do checksum
+    sum = 0;
+
+    for(int i = 0; i < tableHeader->Length; i ++) {
+        sum += ((char*) tableHeader)[i];
+    }
+
+    if( sum != 0)
+        printf("Table invalid!");*/
+}

kernel/acpi/acpi.h

@@ -0,0 +1,14 @@
+#pragma once 
+#include "rsdp.h"
+class ACPI {
+    public:
+        static void initialize();
+        
+        // In the future ACPI might start
+        // doing more systems initialization
+
+    static RSDPDescriptor* rsd_ptr;
+    static RSCPDescriptor20* rsd2_ptr;
+    static RSDT* rsd_table;
+    private:
+};

kernel/acpi/rsdp.cpp

@@ -0,0 +1,44 @@
+#include "rsdp.h"
+#include "../memory/VirtualMemoryManager.h"
+#include "../../CoreLib/Memory.h"
+
+
+void printRSD(RSDPDescriptor* rsd){
+    printf("Signature: ");
+    for(int i = 0; i < 8; i++){
+        kterm_put(rsd->signature[i]);
+    }
+    kterm_put('\n');
+
+    printf("OEMID: ");
+    for(int i =0; i < 6 ; i++){
+        kterm_put (rsd->OEMID[i]);
+    }
+    kterm_put('\n');
+
+    printf("Revision: %d\n", rsd->Revision);
+}
+
+RSDPDescriptor* FindRSD(){
+    char* memory_byte = (char*) 0x000f2e14;
+    const void* string = "RSD PTR ";
+
+
+    for( ; (uint32_t) memory_byte < 0x0100000; memory_byte+=10){
+        if( memcmp(memory_byte , string , 8 ) ==  0 ) {
+        printf("RSD PTR found at 0x%x !\n", memory_byte);
+        return (RSDPDescriptor*) memory_byte;
+        break;
+        }
+    }
+
+    memory_byte = (char*) 0x000E0000;
+    for ( ;(uint32_t) memory_byte < 0x000FFFFF; memory_byte += 1)
+    {
+        if( memcmp(memory_byte , string , 8 ) ==  0 ) {
+            printf("RSD PTR found at 0x%x !\n", memory_byte);
+            return (RSDPDescriptor*) memory_byte;
+            break;
+        }
+    }
+}

kernel/acpi/rsdp.h

@@ -0,0 +1,45 @@
+#pragma once
+#include "../terminal/kterm.h"
+#include <CoreLib/Memory.h>
+#include <stdint-gcc.h>
+
+
+struct ACPISDTHeader{
+    char Signature[4];
+    uint32_t Length;
+    uint8_t Revision;
+    uint8_t CheckSum;
+    char OEMID[6];
+    char OEMTableID[8];
+    uint32_t OEMRevision;
+    uint32_t CreatorID;
+    uint32_t CreatorRevision;
+};
+
+struct RSDT{
+    struct ACPISDTHeader h;
+    uint32_t *PointerToSDT; // Length of array : (header.Length - sizeof(header))/ 4
+}__attribute__((packed));
+
+
+struct RSDPDescriptor {
+    char signature[8];
+    uint8_t Checksum ;
+    char OEMID [6];
+    uint8_t Revision;
+    uint32_t RsdtAddress;
+}__attribute__((packed));
+
+struct RSCPDescriptor20{
+   RSDPDescriptor base;
+   uint32_t Length;
+   uint64_t XsdtAddress;
+   uint8_t ExtendedChecksum;
+   uint8_t reserved[3];
+}__attribute__((packed));
+
+RSDPDescriptor* FindRSD();
+
+void printRSD(RSDPDescriptor* rsd);
+
+RSDT* getRSDT(RSDPDescriptor* rsd);

kernel/bitmap.h

@@ -0,0 +1,38 @@
+#pragma once 
+#include <stddef.h>
+#include <stdint.h>
+
+inline void bitmap_set( uint32_t* map , int index )
+{
+    map[index/32] |= (1 << (index % 32));
+}
+
+inline void bitmap_unset(uint32_t* map , int index)
+{
+    map[index/32] &= ~(1 << (index % 32));
+}
+
+inline uint32_t bitmap_first_unset( uint32_t* map , int map_size)
+{
+    for ( int i = 0 ; i < map_size ; i ++ )
+    {
+        // 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] & (0x00000001 << j)) > 0)
+                {
+                    return (i*32)+j;
+                }
+            }
+
+        
+        }
+
+
+    }
+
+    return -1;
+    
+}

kernel/boot/boot.s

@@ -0,0 +1,130 @@
+.include "./boot/multiboot.s"
+/*
+*	Allocate initial stack
+*/
+.section .bootstrap_stack, "aw", @nobits
+stack_bottom:
+.skip 16384 # 16 KiB
+.globl stack_top
+stack_top:
+
+/*
+* Preallocate a couple pages to get us bootstrapped 
+* Being carefull to not use any address the bootloader might 
+* be using for its multiboot structures
+*/
+.section .bss, "aw", @nobits
+	.align 4096
+.globl boot_page_directory
+boot_page_directory:
+	.skip 4096
+.globl boot_page_table
+boot_page_table:
+	.skip 4096
+.globl multiboot_page_table
+multiboot_page_table:
+	.skip 4096
+# More page tables may be required
+
+# Entry point
+.section .multiboot.text, "a"
+.globl _start
+.type _start, @function 
+_start:
+
+	# Get physical address of the boot_page_table
+	movl $(boot_page_table - 0xC0000000), %edi
+	# Map address 0
+	movl $0, %esi
+1:	
+	cmpl $(kernel_end - 0xC0000000), %esi
+	jge 3f
+
+	# Map physical address as "present and writable"
+	movl %esi, %edx
+	orl $0x003, %edx
+	movl %edx, (%edi)
+
+2: # Size of page is 4096 bytes
+	addl $4096, %esi
+	# Size of entries in boot_page_table is 4 bytes
+	addl $4, %edi 
+	# Loop to the next entry if we haven't finished.
+	loop 1b
+
+3:	# Map VGA video memory to 0xC03FF00 as "present, writable"
+	movl $(0x000B8000 | 0x003), boot_page_table - 0xC0000000 + 1023 * 4
+
+	# Map the page table to both virtual addresss 0x00000000 and 0xC0000000
+	movl $(boot_page_table - 0xC0000000 + 0x003), boot_page_directory - 0xC0000000 + 0
+	movl $(boot_page_table - 0xC0000000 + 0x003), boot_page_directory - 0xC0000000 + 768 * 4
+
+	# Set cr3 to the address of the boot_page_directory
+	movl $(boot_page_directory - 0xC0000000), %ecx
+	movl %ecx, %cr3
+
+	# Enable paging and the write-protect bit
+	movl %cr0, %ecx
+	orl $0x80010000, %ecx
+	movl %ecx, %cr0
+
+	# Jump to higher half with an absolute jump
+	lea 4f, %ecx
+	jmp *%ecx
+
+.section .text
+4:
+	# At this point, paging is fully set up and enabled
+isPaging:
+
+	# Reload cr3 to force tlb flush 
+	movl %cr3, %ecx
+	movl %ecx, %cr3
+
+	/*Setup the stack pointer to point to the beginning of our stack */
+	/* I believe its a high address growing down to lower adress for the stack on x86*/
+	mov $stack_top, %esp
+
+	/*Reset EFLAGS*/
+	pushl $0 
+	popf 
+
+	
+	/* push the pointer to the Multiboot information structure*/
+	pushl %ebx
+
+	/* push the magic value */
+	pushl %eax
+	call prekernelSetup
+
+	# Unmap the identity mapping as it is now unnecessary  
+	# movl $0, boot_page_directory + 0
+
+
+	call kernel
+
+	cli
+1:	hlt
+	jmp 1b
+
+
+.include "./memory/gdt/gdt.s"
+.include "./irs_table.s"
+.include "./irq_table.s"
+.include "./interrupts/idt.s"
+
+.globl jump_usermode
+jump_usermode:
+    mov $((4*8) | 3) , %ax
+    mov %ax, %ds
+    mov %ax, %es
+    mov %ax, %fs
+    mov %ax, %gs
+
+    mov %esp, %eax
+    push $( (3*8) | 3)
+    push %eax
+    pushf
+    push $( ( 3 * 8) | 3)
+    push startSuperVisorTerminal
+    iret

kernel/boot/multiboot.s

@@ -0,0 +1,15 @@
+/*
+ * Multiboot 
+ */
+.set ALIGN,    1<<0             /* align loaded modules on page boundaries */
+.set MEMINFO,  1<<1             /* provide memory map */
+.set FLAGS,    ALIGN | MEMINFO  /* this is the Multiboot 'flag' field */
+.set MAGIC,    0x1BADB002       /* 'magic number' lets bootloader find the header */
+.set CHECKSUM, -(MAGIC + FLAGS) /* checksum of above, to prove we are multiboot */
+
+.section .multiboot.data, "aw"
+.align 4
+.long MAGIC
+.long FLAGS
+.long CHECKSUM
+ 

kernel/bootcheck.h

@@ -1,8 +1,8 @@
 #pragma once 
-#include "bootloader/multiboot.h"
+#include "prekernel/multiboot.h"
 #define CHECK_FLAG(flags, bit) ((flags) & (1 <<(bit)))
 
-#include "tty/kterm.h"
+#include "terminal/kterm.h"
 
 
 
@@ -10,66 +10,81 @@ void CheckMBT ( multiboot_info_t*  mbt  ){
       /* Set MBI to the addresss of the multiboot information structure*/
         multiboot_info_t * mbi = (multiboot_info_t *) mbt;
 
+#ifdef __VERBOSE__
         /* Print out the flags */
         printf("flags = 0x%x\n", (unsigned) mbi->flags);
-
+#endif
         /* Are mem_* valid? */
         if ( CHECK_FLAG(mbi->flags,0)){
-            printf("mem_lower = %uKB, mem_upper = %uKB\n");
+                // Do nothing
         }
 
         /* is boot device valid ? */
-        if (CHECK_FLAG (mbi->flags, 1)){
+        if (CHECK_FLAG (mbi->flags, 1))
+        {
+#ifdef __VERBOSE__
             printf("boot_device = 0x0%x\n", (unsigned) mbi->boot_device);
+#endif
         }
 
         /* is the command line passed? */
-        if (CHECK_FLAG ( mbi->flags,2)){
+        if (CHECK_FLAG ( mbi->flags,2))
+        {
+#ifdef  __VERBOSE__
             printf("cmdline = %s\n", (char *) mbi->cmdline);
+#endif
         }
 
         /* Are mods_* valid? */
         if(CHECK_FLAG ( mbi->flags, 3)){
             multiboot_module_t *mod;
             uint32_t i;
-
+#ifdef __VERBOSE__
             printf("mods count = %d, mods_addr = 0x%x\n", (int) mbi->mods_count, (int) mbi->mods_addr);
 
             for(i = 0, mod = (multiboot_module_t *) mbi->mods_addr; i < mbi->mods_count; i++ , mod++){
                 printf(" mod start = 0x%x, mod_end = 0x%x, cmdline = %s\n", (unsigned) mod->mod_start, (unsigned) mod->mod_end, (char*) mod->cmdline);
             }
+#endif
         }
 
         /* Bits 4 and 5 are mutually exclusive! */
-        if (CHECK_FLAG (mbi->flags, 4) && CHECK_FLAG(mbi->flags, 5)){
+        if (CHECK_FLAG (mbi->flags, 4) && CHECK_FLAG(mbi->flags, 5))
+        {
+#ifdef __VERBOSE__
             printf("Both bits 4 and 5 are set.\n");
+#endif 
             return;
         }
 
         /* Is the symbol table of a.out valid? */
         if (CHECK_FLAG(mbi->flags, 4)){
             multiboot_aout_symbol_table_t *multiboot_aout_sym = &(mbi->u.aout_sym);
-
+#ifdef __VERBOSE__
             printf( "multiboot_aout_symbol_table: tabsize = 0x%0x, strsize = 0x%x, addr = 0x%x\n", 
             (unsigned) multiboot_aout_sym->tabsize,
             (unsigned) multiboot_aout_sym->strsize,
             (unsigned) multiboot_aout_sym->addr);
-
+#endif
         }
 
         /* Is the section header table of ELF valid? */
         if (CHECK_FLAG(mbi->flags, 5)){
             multiboot_elf_section_header_table_t *multiboot_elf_sec = &(mbi->u.elf_sec);
-
+#ifdef __VERBOSE__
             printf("multiboot_elf_sec: num = %u, size = 0x%x, addr = 0x%x, shnd = 0x%x\n",
+            
             (unsigned) multiboot_elf_sec->num, (unsigned) multiboot_elf_sec->size,
             (unsigned) multiboot_elf_sec->addr, (unsigned)  multiboot_elf_sec->shndx);
+#endif
             
         }
 
         /* Draw diagonal blue line */
         if (CHECK_FLAG (mbt->flags, 12)){
-            printf("Can draw!");
+#ifdef __VERBOSE__
+            printf("Can draw!\n");
+#endif
         } 
 
 

kernel/bootinfo.h

@@ -0,0 +1,9 @@
+#pragma once
+#include "memory/memoryinfo.h"
+
+
+struct BootInfo{
+    const char* BootStructureID = "BarinkOS";
+    MemoryInfo* memory;
+
+}; 

kernel/definitions.h

@@ -0,0 +1,9 @@
+#pragma once 
+/**
+ * Kernel definitions
+ */
+
+#define __DEBUG__ false
+#define KERNEL_VERSION 0.03
+
+#define ARCHITECTURE "I386"

kernel/devices/BlockDevice.h

@@ -0,0 +1,11 @@
+//
+// Created by nigel on 21/02/23.
+//
+#pragma once
+
+class BlockDevice {
+    virtual char* Read()=0;
+    virtual void Write() =0;
+};
+
+

kernel/devices/CharacterDevice.h

@@ -0,0 +1,11 @@
+//
+// Created by nigel on 21/02/23.
+//
+#pragma once
+
+class CharacterDevice {
+    virtual char Read()=0;
+    virtual void Write()=0;
+};
+
+

kernel/drivers/cmos/cmos.cpp

@@ -0,0 +1,38 @@
+void ReadFromCMOS(unsigned char array[])
+{
+    unsigned char tvalue, index;
+
+    for (index = 0; index < 128; index++)
+    {
+        asm(
+            "cli\n\t"           // Disable interrupts
+            "mov al, index\n\t" // Move index address
+            // since the 0x80 bit of al is not set, NMI is active 
+            "out 0x70,al\n\t" // Copy address to CMOS register
+            // some kind of real delay here is probably best 
+            "in al,0x71\n\t" // Fetch 1 byte to al
+            "sti\n\t"        // Enable interrupts
+            "mov tvalue,al\n\t");
+
+        array[index] = tvalue;
+    }
+}
+
+void WriteTOCMOS(unsigned char array[])
+{
+   unsigned char index;
+ 
+   for(index = 0; index < 128; index++)
+   {
+      unsigned char tvalue = array[index];
+      
+       asm("cli\n\t"       // Clear interrupts
+         "mov al,index\n\t"    // move index address
+         "out 0x70,al\n\t"     // copy address to CMOS register
+         // some kind of real delay here is probably best 
+         "mov al,tvalue\n\t"   // move value to al
+         "out 0x71,al\n\t"   // write 1 byte to CMOS
+         "sti\n\\t"   );        // Enable interrupts
+      
+   }
+}

kernel/drivers/pic/pic.h

@@ -1,5 +1,7 @@
-#pragma once 
-#include "../io.h"
+#pragma once
+
+#include <stdint-gcc.h>
+#include "../../io/io.h"
 
 #define PIC1		0x20		/* IO base address for master PIC */
 #define PIC2		0xA0		/* IO base address for slave PIC */

kernel/drivers/pit/pit.cpp

@@ -0,0 +1,54 @@
+#include "pit.h"
+#include "../../terminal/kterm.h"
+uint32_t pit_tick = 0;
+
+
+void pit_initialise()
+{
+    asm volatile("CLI");
+
+#ifdef __VERBOSE__
+    printf("Init PIT!\n");
+#endif
+    // clear mask for IRQ 0 
+    uint8_t value = inb(0x21) & ~(1<< 0);
+    outb(0x21, value);
+
+    io_wait();
+
+    const int freq = 500;
+
+    uint32_t divisor = 1193180 / freq;
+
+    outb(PIT_COMMAND, 0x36);
+
+    uint8_t l = (uint8_t) (divisor & 0xFF);
+    uint8_t h = (uint8_t) ( (divisor>>8) & 0xff);
+
+    outb(PIT_DATA_0, l);
+    outb(PIT_DATA_0,h);
+
+
+    asm volatile("STI");
+}
+
+
+void get_pit_count()
+{
+    asm volatile ("CLI");
+
+    outb(PIT_COMMAND, 0);
+    uint16_t count = inb(PIT_DATA_0);
+    count |= inb(PIT_DATA_0) << 8;
+
+    printf("PIT count: 0x%x\n", count); 
+
+    asm volatile("STI");   
+
+}
+
+void set_pit_count()
+{
+
+}
+

kernel/drivers/pit/pit.h

@@ -0,0 +1,18 @@
+#pragma once 
+#include <stdint-gcc.h>
+#include "../../io/io.h"
+#define PIT_DATA_0 0x40
+#define PIT_DATA_1 0x41
+#define PIT_DATA_2 0x42
+#define PIT_COMMAND 0x43
+
+
+extern uint32_t pit_tick;
+
+
+void pit_initialise();
+
+
+void get_pit_count();
+
+void set_pit_count();

kernel/drivers/ps-2/keyboard.cpp

@@ -0,0 +1,51 @@
+#include "keyboard.h"
+
+KeyPressInfo keyPress {};
+
+void KeyHandled(){
+    keyPress.ScanCode= 0x00;
+    keyPress.PressedModifiers = 0x00;
+}
+
+
+char getASCIIKey(){
+    char keyPressed;
+    // Wait until a key is pressed  
+    while(keyPress.ScanCode == 0x00) {
+        asm volatile ("NOP");
+    }
+
+    
+    // Translate keycode to ascii 
+    // Probably a lookup table might be handy 
+    // Until 0x37
+     const char* ASCIILookUp =
+      "\01234567890-=\0\0QWERTYUIOP[]\0\0ASDFGHJKL;\'`\0\\ZXCVBNM,./\0"; 
+     
+     uint8_t ASCII_Index = keyPress.ScanCode - 3  ;
+     //printf("ASCII_INDEX: %x\n", ASCII_Index);
+     keyPressed = ASCIILookUp[ASCII_Index];
+
+    KeyHandled();
+
+    return keyPressed;
+}
+
+
+
+uint8_t getKey(){
+    // Wait until a key is pressed 
+    while(keyPress.ScanCode == 0x00){
+        asm volatile ("NOP");
+    }
+    
+    if( keyPress.ScanCode > 0x37){
+        keyPress.ScanCode = 0x00;
+        return 0;
+    }
+
+    uint8_t ScanCode = keyPress.ScanCode;
+   // KeyHandled();
+
+    return  ScanCode ;
+}

kernel/drivers/ps-2/keyboard.h

@@ -0,0 +1,34 @@
+#pragma once
+#include <stdint.h>
+#include "../../terminal/kterm.h"
+enum ScanCodeSet {
+    None            =   0,
+    ScanCodeSet1    =   1,
+    ScanCodeSet2    =   2,
+    ScanCodeSet3    =   3,
+};
+
+enum Modifiers {
+    LSHIFT  =   1,
+    RSHIFT  =   2,
+
+    LCTRL   =   3,
+    RCTRL   =   4,
+
+    LALT    =   5,
+    RALT    =   6
+};
+
+struct KeyPressInfo{ 
+    uint8_t PressedModifiers;
+    uint8_t ScanCode;
+};
+
+
+
+extern KeyPressInfo keyPress;
+
+void KeyHandled();
+
+char getASCIIKey();
+uint8_t getKey();

kernel/grub.cfg

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

kernel/i386/README.md

@@ -0,0 +1,2 @@
+# architecture specific implementations 
+## This will contain I386 Architecture specific implementations

kernel/i386/processor.cpp

@@ -0,0 +1,127 @@
+//
+// Created by nigel on 17/02/23.
+//
+
+#include "processor.h"
+
+
+uint32_t processor::cap_page;
+uint32_t processor::cap_page1;
+uint32_t processor::cap_page7 ;
+
+void processor::initialize()
+{
+
+    asm volatile ("movl $0x80000001, %%eax;"
+                  "CPUID;"
+                  "movl %%edx, %0"
+                  :: "m"(cap_page));
+
+    asm volatile ("movl $0x01, %%eax; "
+                  "CPUID;"
+                  "movl %%edx, %0"
+                  :: "m"(cap_page1));
+
+    asm volatile ("movl $0x07, %%eax;"
+                  "movl $0x0, %%ecx;"
+                  "CPUID;"
+                  "movl %%edx, %0"
+                  :: "m"(cap_page7));
+
+}
+
+bool processor::hasAMXExtension()
+{
+    return (cap_page7 & AMX_TYPE::AMX_BF16) || (cap_page7 & AMX_TYPE::AMX_TILE) || (cap_page7 & AMX_TYPE::AMX_INT8);
+}
+
+
+/*
+ * PSE: page-size extensions for 32-bit paging.
+ * If CPUID.01H:EDX.PSE [bit 3] = 1, CR4.PSE may be set to 1, enabling support for 4-MByte pages with 32-bit paging
+ */
+bool processor::has32bitPagingSupport() {
+    // is the PSE bit set
+    return cap_page1 & (0x1 << 3);
+}
+
+/*
+ * PAE: physical-address extension.
+ * If CPUID.01H:EDX.PAE [bit 6] = 1, CR4.PAE may be set to 1, enabling PAE paging (this setting is also required
+ * for 4-level paging and 5-level paging).
+ */
+bool processor::hasPAEExtension(){
+    return cap_page1 & (0x1 << 6);
+}
+
+/*
+ * PGE: global-page support.
+ * If CPUID.01H:EDX.PGE [bit 13] = 1, CR4.PGE may be set to 1, enabling the global-page feature (see Section
+ * 4.10.2.4).
+ */
+bool processor::hasPageSupport(){
+    return cap_page1 & (0x1 << 13);
+}
+
+/*
+ * Page1GB: 1-GByte pages.
+ * If CPUID.80000001H:EDX.Page1GB [bit 26] = 1, 1-GByte pages may be supported with 4-level paging and 5-
+ * level paging (see Section 4.5).
+ */
+bool processor::gigabytePages() {
+    return cap_page & (0x1 << 26);
+}
+
+void processor::enable_protectedMode()
+{
+    // Set the protected bit of control register 0
+    // this will put the CPU into protected mode
+    // NOTE: This should really be an assembly procedure
+    // We cant directly write to control register 0
+    // therefor we copy the value of control register 0 into eax
+    // once we are done manipulating the value we write the value in
+    // eax back to control register 0
+
+    asm volatile("mov %cr0, %eax ");
+    asm volatile("or $1, %eax");
+    asm volatile("mov %eax, %cr0");
+}
+
+
+
+uint32_t processor::GetEFLAGS()
+{
+    uint32_t EFLAGS = 0;
+    asm volatile ("pushfl;" "movl 4(%%esp), %%edx" : "=d"(EFLAGS));
+    return EFLAGS;
+}
+
+
+uint32_t processor::GetCR0()
+{
+    uint32_t cr0_value;
+    asm volatile ("movl %%cr0, %%edx" : "=d"(cr0_value));
+    return cr0_value;
+
+}
+
+
+uint32_t processor::GetCR2(){
+    uint32_t cr2_value;
+    __asm__ volatile("movl %%cr2, %%edx": "=d"(cr2_value));
+    return cr2_value;
+}
+
+
+uint32_t processor::GetCR3(){
+    uint32_t cr3_value;
+    __asm__ volatile("movl %%cr3, %%edx": "=d"(cr3_value));
+    return cr3_value;
+}
+
+
+uint32_t processor::GetCR4(){
+    uint32_t cr4_value;
+    __asm__ volatile("movl %%cr4, %%edx": "=d"(cr4_value));
+    return cr4_value;
+}

kernel/i386/processor.h

@@ -0,0 +1,36 @@
+//
+// Created by nigel on 17/02/23.
+//
+#pragma  once
+#include "../terminal/kterm.h"
+class processor {
+public:
+    static void initialize();
+
+    // Based on information from https://en.wikichip.org/wiki/x86/amx#Detection
+    enum  AMX_TYPE{
+        AMX_BF16 = (0x1 << 22),
+        AMX_TILE = (0x1 << 24),
+        AMX_INT8 = (0x1 << 25)
+    };
+    static bool hasAMXExtension();
+    static bool has32bitPagingSupport();
+    static bool hasPageSupport();
+    static bool gigabytePages();
+
+    static bool hasPAEExtension();
+    static void enable_protectedMode();
+
+    static uint32_t GetEFLAGS();
+    static uint32_t GetCR0();
+    static uint32_t GetCR2();
+    static uint32_t GetCR3();
+    static uint32_t GetCR4();
+
+private:
+    static uint32_t cap_page;
+    static uint32_t cap_page1;
+    static uint32_t cap_page7;
+
+
+};

kernel/interrupts/idt.cpp

@@ -0,0 +1,427 @@
+#include "idt.h"
+#include "../drivers/pit/pit.h"
+#include "../drivers/ps-2/keyboard.h"
+#include "../i386/processor.h"
+#include "../memory/VirtualMemoryManager.h"
+#include "../syscalls.h"
+
+
+IDT_entry idt_table[256];
+IDT_ptr idt_ptr;
+
+
+void set_id_entry (uint8_t num , uint32_t base, uint16_t sel,  uint8_t flags){
+    idt_table[num].offset_1 = base & 0xFFFF;
+    idt_table[num].selector = sel;
+    idt_table[num].zero = 0;
+    idt_table[num].type_attr = flags;
+    idt_table[num].offset_2 = (base >> 16) & 0xFFFF;
+
+};
+
+void irs_handler (registers* regs) {
+     uint32_t FaultingAddress;
+        printf("(IRS) Interrupt number: %d \n EAX: ", regs->int_no, regs->eax);
+        switch (regs->int_no)
+        {
+        case 0:
+            // Divide Error #DE
+            printf("#DE\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp);
+        break;
+        
+        case 1:
+            // Debug Exception #DB
+            printf("#DB\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp);
+        break;
+
+        case 2:
+            // NMI Interrupt 
+            printf("#NMI\n");
+        break;
+        
+        case 3:
+            // Breakpoint Exception #BP
+            printf("#BP\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp);
+        break;
+        
+        case 4:
+            // Overflow Exception #OF
+            printf("#OF\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp);
+        break;
+        
+        case 5:
+            // BOUND Range Exceeded Exception #BR
+            printf("#BR\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp);
+        break;
+        
+        case 6:
+            // Invalid OpCode Exception #UD 
+            printf("#UD\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp);
+        break;
+        
+        case 7:
+            // Device Not Available Exception  #NM
+            printf("#NM\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp);
+        break;
+        
+        case 8:
+            // Double Fault Exception #DF
+            printf("#DF\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp);
+            while(true);
+        break;
+
+        case 9:
+            // Coprocessor Segment Overrun
+            printf("Coprocessor Segment overrun!\n");
+        break;
+        
+        case 10:
+            // Invalid TSS Exception #TS
+            printf("#TS\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp);
+            __asm__("cli;" "1: hlt;" "jmp 1b;");
+        break;
+
+        case 11:
+            // Segment Not Present #NP
+            printf("#NP\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp);
+        break;
+        
+        case 12:
+            // Stack Fault Exception #SS
+            printf("#SS\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp);
+        break;
+        
+        case 13:{
+            // General Protection Exception #GP
+            printf("#GP\n");
+
+            printf("Accessing memory caused a general protection exception.\n");
+            printf("Faulting instruction at addres: 0x%x\n", regs->eip );
+            printf("Error code: 0x%x\n", regs->err_code);
+
+            if (regs->err_code != 0){
+                printf("Fault due to entry at index: 0x%x (%d)\n", (regs->err_code >> 3 & 0xFFF ) , regs->err_code);
+
+
+                uint8_t table = regs->err_code >> 1 & 0x3 ;
+                
+                if(table == 0   ){
+                    printf("* Index references GDT\n");
+                }
+                if(table == 1  ){
+                    printf("* Index references IDT\n");
+                }
+
+                if(table  == 2   ){
+                    printf("* Index references LDT\n");
+                }
+
+                if(table  == 3 ){
+                    printf("* Index references IDT\n");
+                }
+
+                if( regs->err_code & 0x1)
+                {
+                    printf("* Originated externally!\n");
+                }
+            }
+
+            __asm__("cli;" "1: hlt;" "jmp 1b;");
+
+        }
+        break;
+        
+        case 14:
+            // Page Fault Exception #PF
+            printf("#PF\n");
+            #define ALIGN(addr, align) (((addr) & ~((align) - 1)) + (align))
+            FaultingAddress = processor::GetCR2();
+            
+            printf("Accessing the linear address 0x%x resulted in a page fault!\n\n", FaultingAddress);
+        
+            // Error code of 32 bits are on the stack
+            // CR2 register contains the 32-bit linear virtual address that generated the exception
+            // See Intel Software Developers manual Volume 3A Part 1 page 236 for more info
+            #define PF_ERR_PRESENT_BIT 0x1
+            #define PF_ERR_WRITE_BIT 0x2
+            #define PF_ERR_USER_BIT 0x3
+            #define PF_ERR_RESERVERD_WRITE_BIT 0x4
+            #define PF_ERR_INSTRUCTION_FETCH_BIT 0x5
+            #define PF_ERR_PROTECTION_KEY_BIT 0x6
+            #define PF_ERR_SHADOW_STACK_BIT 0x7
+            #define PF_ERR_SOFTWARE_GUARD_EXTENSION_BIT 0xE
+
+            printf("REASON: \n\n");
+
+         
+            if (regs->err_code & PF_ERR_PRESENT_BIT ){
+                printf("* Page protection violation!\n");
+            } else{
+                printf("* Page not-present!\n");
+                //Immediate_Map(FaultingAddress, FaultingAddress);
+             
+            }
+
+            if(regs->err_code & PF_ERR_WRITE_BIT){
+                printf("* Write access violation!\n");
+            } else{
+                printf("* Read access violation!\n");
+            }
+
+            if(regs->err_code & PF_ERR_USER_BIT){
+                printf("* Violation from user-space (CPL=3)\n");
+            }
+
+            if(regs->err_code & PF_ERR_INSTRUCTION_FETCH_BIT){
+                printf("* Caused by an instruction fetch. \n");
+            }
+
+
+            __asm__("cli;" "1: hlt;" "jmp 1b;");
+
+        break;
+        
+        case 16:
+            // x87 FPU Floating-point Error #MF
+            printf("#MF\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp);
+        break;
+        
+        case 17:
+            // Alignment Check Exception #AC
+            printf("#AC\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp); 
+        break;
+        
+        case 18:
+            // Machine-Check Exception #MC
+            printf("#MC\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp); 
+        break;
+        
+        case 19:
+            // SIMD Floating-point Exception #XM
+            printf("#XM\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp); 
+        break;
+        
+        case 20:
+             // Virtualization Exception #VE
+            printf("#VE\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp); 
+        break;
+        
+        case 21:
+             // Control Protection Exception #CP
+            printf("#CP\n");
+            printf("EIP: 0x%x\n", regs->eip);
+            printf("EAX: 0x%x\n", regs->eax);
+            printf("EBP: 0x%x\n", regs->ebp); 
+        break;
+
+        case 50:
+            printf("SYSTEMCALL\n");
+            printf("EAX 0x%x\n", regs->eax);
+
+                switch (regs->eax) {
+                    case 0x0:
+                        printf("test!\n");
+                        break;
+                    case 0x5:
+                        sys_open();
+                        break;
+                    case 0x10:
+                        sys_read((FILE*)regs->ebx, (char*)regs->ecx);
+                        break;
+                    case 0x20:
+                        sys_write((FILE*)regs->ebx, (const char*)regs->ecx, regs->edx);
+                        break;
+                    case 0x666:
+                        sys_version();
+                        break;
+
+                };
+        break;
+        default:
+            // PANIC!!!
+            break;
+        }
+        
+      
+        
+}
+
+void irq_handler (registers regs) {
+    switch (regs.int_no) {
+    case 0:
+            pit_tick++;
+        break;
+    case 1:
+        // Keyboard interrupt !!
+
+        int scan;
+        int i;/*register*/
+
+        // Read scancode 
+        scan = inb(0x60);
+        
+        // Send ack message!
+        i = inb(0x61);
+        outb(0x61, i|0x80);
+        outb(0x61, i);
+
+        // NOTE: check for special scan codes 
+        // e.g. modifiers etc..
+        if( scan < 0x37){
+            //printf("Read from IO: 0x%x\n", scan);
+            keyPress.ScanCode = scan ;
+            //printf( "[From Interrupt] Scancode: %x\n", keyPress.ScanCode);
+
+        }
+
+        
+        break;    
+    case 12:
+        // PS2 Mouse interrupt 
+        printf("Mouse event triggered!");
+        //int event = inb(0x60);
+        break;
+
+    default:
+        //printf("Interrupt happened!");
+        //printf("Received INT: 0x%x\n", regs.int_no);
+        break;
+    }        
+
+    outb(0x20, 0x20); // send end of interrupt to master
+
+    if ( regs.int_no > 8 && regs.int_no <= 15) {
+        outb(0xA0, 0x20); // send end of interrupt to slave 
+    }
+    
+    
+    if( regs.int_no == 13){
+        printf(" Error code: %d \n", regs.err_code);
+
+    }
+
+}
+
+void initidt(){
+    // Initialize the IDT pointer
+    idt_ptr.length = sizeof(IDT_entry) * 255;
+    idt_ptr.base = (uint32_t)&idt_table;
+
+#ifdef __VERBOSE__
+    printf("Init IDT\n");
+#endif
+
+    // TODO: Set everything to zero first
+
+    set_id_entry(0,  (uint32_t) irs0 , 0x08, 0x8F);
+    set_id_entry(1,  (uint32_t) irs1 , 0x08, 0x8E);
+    set_id_entry(2,  (uint32_t) irs2 , 0x08, 0x8E);
+    set_id_entry(3,  (uint32_t) irs3 , 0x08, 0x8E);
+    set_id_entry(4,  (uint32_t) irs4 , 0x08, 0x8E);
+    set_id_entry(5,  (uint32_t) irs5 , 0x08, 0x8E);
+    set_id_entry(6,  (uint32_t) irs6 , 0x08, 0x8E);
+    set_id_entry(7,  (uint32_t) irs7 , 0x08, 0x8E);
+    set_id_entry(8,  (uint32_t) irs8 , 0x08, 0x8E);
+    set_id_entry(9,  (uint32_t) irs9 , 0x08, 0x8E);
+    set_id_entry(10, (uint32_t) irs10 , 0x08, 0x8E);
+    set_id_entry(11, (uint32_t) irs11 , 0x08, 0x8E);
+    set_id_entry(12, (uint32_t) irs12 , 0x08, 0x8E);
+    set_id_entry(13, (uint32_t) irs13 , 0x08, 0x8E);
+    set_id_entry(14, (uint32_t) irs14 , 0x08, 0x8E);
+    set_id_entry(15, (uint32_t) irs15 , 0x08, 0x8E);
+    set_id_entry(16, (uint32_t) irs16 , 0x08, 0x8E);
+    set_id_entry(17, (uint32_t) irs17 , 0x08, 0x8E);
+    set_id_entry(18, (uint32_t) irs18 , 0x08, 0x8E);
+    set_id_entry(19, (uint32_t) irs19 , 0x08, 0x8E); 
+    set_id_entry(20, (uint32_t) irs20 , 0x08, 0x8E);
+    set_id_entry(21, (uint32_t) irs21 , 0x08, 0x8E);
+    set_id_entry(22, (uint32_t) irs22 , 0x08, 0x8E);
+    set_id_entry(23, (uint32_t) irs23 , 0x08, 0x8E);
+    set_id_entry(24, (uint32_t) irs24 , 0x08, 0x8E);
+    set_id_entry(25, (uint32_t) irs25 , 0x08, 0x8E);
+    set_id_entry(26, (uint32_t) irs26 , 0x08, 0x8E);
+    set_id_entry(27, (uint32_t) irs27 , 0x08, 0x8E); 
+    set_id_entry(28, (uint32_t) irs28 , 0x08, 0x8E);
+    set_id_entry(29, (uint32_t) irs29 , 0x08, 0x8E);
+    set_id_entry(30, (uint32_t) irs30 , 0x08, 0x8E);
+    set_id_entry(31, (uint32_t) irs31 , 0x08, 0x8E);
+
+    set_id_entry(0x50, (uint32_t) irs50, 0x08, 0x8E);
+    //print_serial("Remapping PIC\n");
+    PIC_remap(0x20, 0x28);
+
+    // clear mask for IRQ 12
+    uint8_t value = inb(0x21) & ~(1<< 12);
+    outb(0x21, value);
+
+
+
+    // pic IRQ Table
+    set_id_entry(32, (uint32_t)irq0, 0x08, 0x8E);
+    set_id_entry(33, (uint32_t)irq1, 0x08, 0x8E); // PS2 Keyboard
+    set_id_entry(34, (uint32_t)irq2, 0x08, 0x8E);
+    set_id_entry(35, (uint32_t)irq3, 0x08, 0x8E);
+    set_id_entry(36, (uint32_t)irq4, 0x08, 0x8E);
+    set_id_entry(37, (uint32_t)irq5, 0x08, 0x8E);
+    set_id_entry(38, (uint32_t)irq6, 0x08, 0x8E);
+    set_id_entry(39, (uint32_t)irq7, 0x08, 0x8E);
+    set_id_entry(40, (uint32_t)irq8, 0x08, 0x8E);
+    set_id_entry(41, (uint32_t)irq9, 0x08, 0x8E);
+    set_id_entry(42, (uint32_t)irq10, 0x08, 0x8E);
+    set_id_entry(43, (uint32_t)irq11, 0x08, 0x8E);
+    set_id_entry(44, (uint32_t)irq12, 0x08, 0x8E); // PS2 Mouse
+    set_id_entry(45, (uint32_t)irq13, 0x08, 0x8E);
+    set_id_entry(46, (uint32_t)irq14, 0x08, 0x8E);
+    set_id_entry(47, (uint32_t)irq15, 0x08, 0x8E);
+
+    
+    idt_flush((uint32_t)&idt_ptr);
+}

kernel/interrupts/idt.h

@@ -1,11 +1,11 @@
 #pragma once
 
-#include "stdint.h"
-#include "stddef.h"
-#include "../vga/colors.h"
-#include "../pic/pic.h"
+#include <stdint.h>
+#include <stddef.h>
+#include "../drivers/vga/colors.h"
+#include "../drivers/pic/pic.h"
 
-#include "../tty/kterm.h"
+#include "../terminal/kterm.h"
 
 
 extern "C" {
@@ -32,11 +32,11 @@ extern "C" {
 
     extern void idt_flush(uint32_t); 
     void set_id_entry (uint8_t num , uint32_t base, uint16_t sel,  uint8_t flags);
-    void init_idt();
+    void initidt();
 
     void irq_handler (registers regs);
 
-    void irs_handler (registers regs);
+    void irs_handler (registers* regs);
 
     extern void irs0 ();
     extern void irs1 ();
@@ -70,6 +70,7 @@ extern "C" {
     extern void irs29 ();
     extern void irs30 ();
     extern void irs31 ();
+    extern void irs50();
 
 
 

kernel/io/io.cpp

@@ -23,7 +23,7 @@ unsigned int inl_p(unsigned short ){
 }
 
 
-void outb_p(unsigned char , unsigned short ){
+void b_p(unsigned char , unsigned short ){
 
 }
 void outw(unsigned short , unsigned short ){

kernel/irq_table.s

@@ -0,0 +1,55 @@
+.globl irq0
+
+.macro IRQ NAME, VECTOR
+    .globl irq\NAME
+    irq\NAME:
+        cli
+        push $0
+        push \VECTOR
+        jmp irq_common
+.endm
+
+IRQ 0 $0
+IRQ 1 $1
+IRQ 2 $2
+IRQ 3 $3
+IRQ 4 $4
+IRQ 5 $5
+IRQ 6 $6
+IRQ 7 $7
+IRQ 8 $8
+IRQ 9 $9
+IRQ 10 $10
+IRQ 11 $11
+IRQ 12 $12
+IRQ 13 $13
+IRQ 14 $14
+IRQ 15 $15
+
+
+
+irq_common:
+	pusha
+
+	mov %ds, %ax
+	push %eax
+
+	mov $0x10, %ax
+	mov %ax, %ds
+	mov %ax, %es
+	mov %ax, %fs
+	mov %ax, %gs
+
+	call irq_handler
+
+	pop %eax
+
+	mov %ax, %ds
+	mov %ax, %es
+	mov %ax, %fs
+	mov %ax, %gs
+
+	popa
+	add  $8, %esp  # cleans push error and irs code
+	sti
+	iret # pops 5 things at once: CS, EIP, EFLAGS, SS, and ESP

kernel/irs_table.s

@@ -0,0 +1,87 @@
+.code32
+/*
+* Interupt handlers
+*/
+
+.macro ISR_NOERRORCODE NAME, VECTOR
+	.globl irs\NAME
+	irs\NAME:
+		cli 
+		push $0
+		push \VECTOR
+		jmp irs_common
+.endm
+
+.macro ISR_ERROCODE NAME, VECTOR
+	.globl irs\NAME
+	irs\NAME:
+		cli
+		push \VECTOR
+		jmp irs_common
+.endm
+
+
+ISR_NOERRORCODE 0 $0
+ISR_NOERRORCODE 1 $1
+ISR_NOERRORCODE 2 $2
+ISR_NOERRORCODE 3 $3
+ISR_NOERRORCODE 4 $4
+ISR_NOERRORCODE 5 $5
+ISR_NOERRORCODE 6 $6
+ISR_NOERRORCODE 7 $7
+ISR_NOERRORCODE 8 $8
+ISR_NOERRORCODE 9 $9
+ISR_NOERRORCODE 10 $10
+ISR_NOERRORCODE 11 $11
+ISR_NOERRORCODE 12 $12
+ISR_NOERRORCODE 13 $13
+ISR_NOERRORCODE 14 $14
+ISR_NOERRORCODE 15 $15
+ISR_NOERRORCODE 16 $16
+ISR_NOERRORCODE 17 $17
+ISR_NOERRORCODE 18 $18
+ISR_NOERRORCODE 19 $19
+ISR_NOERRORCODE 20 $20
+ISR_NOERRORCODE 21 $21
+ISR_NOERRORCODE 22 $22
+ISR_NOERRORCODE 23 $23
+ISR_NOERRORCODE 24 $24
+ISR_NOERRORCODE 25 $25
+ISR_NOERRORCODE 26 $26
+ISR_NOERRORCODE 27 $27
+ISR_NOERRORCODE 28 $28
+ISR_NOERRORCODE 29 $29
+ISR_NOERRORCODE 30 $30
+ISR_NOERRORCODE 31 $31
+ISR_NOERRORCODE 50 $50
+
+irs_common:
+	pusha 				# Pushes edi,esi,ebp,esp,ebx,edx,ecx,eax
+
+	mov %ds, %ax
+	push %eax
+
+	/* load the kernel data segment descriptor*/
+
+	mov $0x10, %ax
+	mov %ax, %ds
+	mov %ax, %es
+	mov %ax, %fs
+	mov %ax, %gs
+	
+	mov %esp, %eax
+	push %eax 
+
+	call irs_handler
+	
+	pop %eax        // pop stack pointer
+	pop %ebx		// reload ther orignal data segment descriptor
+	mov %bx, %ds
+	mov %bx, %es
+	mov %bx, %fs
+	mov %bx, %gs
+
+	popa
+	add  $8, %esp  # cleans push error and irs code
+
+	iret # pops 5 things at once: CS, EIP, EFLAGS, SS, and ESP

kernel/kernel.cpp

@@ -0,0 +1,82 @@
+/*
+    Copyright © Nigel Barink 2023
+*/
+#include "memory/memory.h"
+#include "memory/KernelHeap.h"
+#include "memory/gdt/gdtc.h"
+#include "memory/TaskStateSegment.h"
+#include "supervisorterminal/superVisorTerminal.h"
+#include "drivers/vga/VBE.h"
+#include "pci/pci.h"
+#include "drivers/pit/pit.h"
+#include "i386/processor.h"
+#include "terminal/kterm.h"
+#include "interrupts/idt.h"
+#include "serial.h"
+#include "storage/vfs/vfs.h"
+#include "storage/filesystems/FAT/FAT.h"
+#include "acpi/acpi.h"
+#include "memory/VirtualMemoryManager.h"
+
+
+extern BootInfoBlock* BIB;
+extern "C"  void LoadGlobalDescriptorTable();
+extern "C" void jump_usermode();
+
+void initBootDrive(){
+    printf("Boot device: 0x%x\n", BIB->bootDeviceID);
+    unsigned int part3 = BIB->bootDeviceID & 0xFF;
+    unsigned int part2 = (BIB->bootDeviceID & 0xFF00) >> 8;
+    unsigned int part1 = (BIB->bootDeviceID & 0xFF0000) >> 16;
+    unsigned int drive = (BIB->bootDeviceID & 0xFF000000) >> 24;
+    if (drive == 0x80 )
+        printf("booted from disk!\n");
+    if(drive == 0x00)
+        printf("booted from floppy disk\n");
+
+    printf("Part1: %d, Part2: %d, Part3: %d\n", part1, part2 , part3);
+    ATAPIO::Identify(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER);
+}
+
+extern "C" void kernel ()
+{
+    init_serial();
+    kterm_init();
+    print_serial("kterm initialized...\n");
+    setup_tss();
+    initGDT();
+    initidt();
+    LoadGlobalDescriptorTable();
+    flush_tss();
+    printf("Memory setup complete!\n");
+    print_serial("Memory initialized....\n");
+    // Enable interrupts
+    asm volatile("STI");
+    initHeap();
+    print_serial("Heap initialized...\n");
+    //pit_initialise();
+
+
+    //ACPI::initialize();
+    //PCI::Scan();
+    processor::initialize();
+    processor::enable_protectedMode();
+    initBootDrive();
+    VirtualFileSystem::initialize();
+
+    print_serial("Run test!");
+#define VFS_EXAMPLE
+#ifdef VFS_EXAMPLE
+    auto fontFile = VirtualFileSystem::open("/FONT    PSF", 0);
+    printf("Size of font file: %d bytes", fontFile->root->size); // COOL This Works like a charm
+#endif
+
+#ifdef USERMODE_RELEASE
+    // Lets jump into user mode
+    jump_usermode();
+#else
+    startSuperVisorTerminal();
+
+#endif
+
+}

kernel/kernel.h

@@ -0,0 +1,8 @@
+#pragma once
+
+#define CHECK_FLAG(flags, bit) ((flags) & (1 <<(bit)))
+#define PANIC(message) {return;} 
+
+
+
+

kernel/linker.ld

@@ -0,0 +1,45 @@
+ENTRY(_start)
+ 
+/* Tell where the various sections of the object files will be put in the final
+   kernel image. */
+SECTIONS
+{
+	. = 0x00100000;  /* place code at 1MB mark*/
+ 
+	_kernel_start	= .;
+	kernel_begin	= .; /*  For legacy reasons */
+	
+	.multiboot.data : {
+		*(.multiboot.data)
+	}
+
+	.multiboot.text : {
+		*(multiboot.text)
+	}
+
+	. += 0xC0000000; /* Addresses in the following code need to be above the 3Gb mark */
+	.text ALIGN (4K) : AT (ADDR (.text) - 0xC0000000)
+	{
+		*(.text)
+	}
+	.rodata ALIGN (4K) : AT (ADDR (.rodata) - 0xC0000000)
+	{
+		*(.rodata)
+		*(.symtab)
+	}
+	.data ALIGN (4K) : AT (ADDR (.data) - 0xC0000000)
+	{
+		*(.data)
+	}
+	.bss ALIGN (4K) : AT (ADDR (.bss) - 0xC0000000)
+	{
+		*(COMMON)
+		*(.bss)
+		*(.bootstrap_stack)
+	}
+
+
+	_kernel_end = .;
+	kernel_end = .; /* For legacy reasons */
+}
+

kernel/memory/KernelHeap.cpp

@@ -0,0 +1,86 @@
+#include "KernelHeap.h"
+#include "VirtualMemoryManager.h"
+extern "C" const uint32_t kernel_end;
+// Size of heap metadata is 5 bytes
+struct heap_block{
+    uint8_t Used;
+    uint32_t Size;
+};
+
+uint32_t heap_size;
+heap_block* start ;
+
+void* malloc(size_t size)
+{
+    //printf("Received request for %d bytes of memory\n", size);
+    heap_block* current = start;
+
+    // look for a free block
+    while(current <  start + heap_size)
+    {
+        if(current->Size >= size && current->Used == false )
+        {
+            // We found a spot 
+           // printf("Block found!\n");
+
+            // Set the spot to in-use 
+            current->Used = true;
+
+
+            // split the block 
+            //printf("Split block.\n");
+            uint32_t oldSize = current->Size;
+            current->Size = size;
+
+            heap_block* new_block = current + sizeof(heap_block) + current->Size;
+            new_block->Size = oldSize - ( sizeof(heap_block) + size);
+            new_block->Used = false;
+
+            // return the free address 
+            // NOTE: added an offset from the initial address to accomodate for 
+            // meta-data.
+            return current + sizeof(heap_block);
+
+        }
+
+        current += current->Size + sizeof(heap_block);
+    }   
+
+    // If we are here we need more memory so we should 
+    // probably ask the VMM for more 
+    // TODO: ask for more memory | Extend kernel heap
+    
+    printf("ERROR: OUT OF HEAP MEMORY CONDITION IS NOT IMPLEMENTED. HEAP NEEDS TO BE EXTENDED!\n");
+}
+
+void free(void* addr)
+{
+    // clear the free boolean that corresponds to this adddress
+    // This should be fairly simple
+    heap_block* allocatedBlock = (heap_block*)((uint32_t)addr - sizeof(heap_block));
+    allocatedBlock->Used = false;
+}
+
+void initHeap()
+{
+    void* HEAP_ADDRESS = allocate_block();
+    printf("0x%x HEAP Paddr\n", HEAP_ADDRESS);
+ 
+    Immediate_Map((uint32_t)HEAP_ADDRESS + 0xC0000000, (uint32_t)HEAP_ADDRESS );
+    start = (heap_block*) ((uint32_t)HEAP_ADDRESS + 0xC0000000);
+    heap_size = 4096;
+
+    printf("Clear heap\n");
+    // Clear the heap 
+    printf("set at 0x%x %d bytes to zero\n", start , heap_size);
+
+    memset((void*)start, 0x00,  heap_size /4);
+
+
+    printf("Init first heap block\n");
+    // initialzie 
+    start->Size = heap_size - sizeof(heap_block);
+
+    start->Used = false;
+
+}

kernel/memory/KernelHeap.h

@@ -0,0 +1,10 @@
+#pragma once 
+#include <stddef.h>
+#include <stdint.h>
+#include "../terminal/kterm.h"
+
+void initHeap();
+
+void* malloc (size_t size );
+void free(void* addr);
+

kernel/memory/PageDirectory.cpp

@@ -0,0 +1,43 @@
+#include "PageDirectory.h"
+
+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;
+    // }
+
+    // // 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.
+    // }
+
+    // // 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 PageDirectory::MapPhysicalToVirtualAddress ( address_t PAddress , address_t VAddress, uint32_t size  )
+{
+
+}

kernel/memory/PageDirectory.h

@@ -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 "./../terminal/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
+
 };

kernel/memory/PhysicalMemoryManager.cpp

@@ -0,0 +1,115 @@
+#include "./PhysicalMemoryManager.h"
+#define IS_ALIGNED(addr, align) !((addr) & ~((align) - 1))
+#define ALIGN(addr, align) (((addr) & ~((align) - 1 )) + (align))
+
+const uint32_t KERNEL_OFFSET = 0xC0000000;
+
+uint32_t* memoryBitMap;
+uint32_t pmmap_size;
+uint32_t max_blocks;
+int used_blocks;
+
+
+void SetupPhysicalMemoryManager(uint32_t mapAddress, uint32_t memorySize ) 
+{
+     /*
+        Every byte contains 8 pages
+        A page is 4096 kib 
+        Every block (1 bit) represent an page 
+    */
+
+    // Set the maximum number of blocks
+    max_blocks = (uint32_t)memorySize / BLOCK_SIZE ;
+    printf("Max Blocks: %d\n", max_blocks);
+    
+    // Set size of the bitmap 
+    uint32_t bitmap_size = max_blocks / 32;
+    printf("Bitmap size: %d bytes\n",bitmap_size);
+
+    // Set blocks used to zero
+    used_blocks = max_blocks;
+    
+    // set the address of the memory bitmap
+    memoryBitMap = (uint32_t*) mapAddress;
+
+    // Set all places in memory as free
+    memset(memoryBitMap, 0xFFFFFFFF,  max_blocks / 32  ); 
+}
+
+// NOTE: This can only give blocks of 4kb at a time!
+//         We might at some point want to allocate multiple blocks at once.
+void* 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 );
+
+    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 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 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 ;
+
+    for( int i = 0; i < NumberOfBlocksToAllocate; i++)
+    {
+        bitmap_unset(memoryBitMap, startBlock + i);// allocate region causes #PF Exception
+        used_blocks++;
+    }
+}
+
+void deallocate_region(uint32_t  StartAddress , uint32_t size ) {
+    // reverse of what happened in allocate_region
+    int NumberOfBlocks = (size / 1024) / 4 / 8 + 1;
+    int startBlock = (StartAddress / 1024) / 4 / 8;
+
+    for(int i = 0; i < NumberOfBlocks; i++)
+    {
+        bitmap_set(memoryBitMap, startBlock + i);
+        used_blocks --;
+    }
+}
+
+int GetUsedBlocks (){
+    return used_blocks;
+}

kernel/memory/PhysicalMemoryManager.h

@@ -0,0 +1,20 @@
+#pragma once
+#include <stddef.h>
+#include <CoreLib/Memory.h>
+
+#include "../prekernel/bootstructure.h"
+#include "../terminal/kterm.h"
+#include "../bitmap.h"
+
+#define BLOCK_SIZE 4092 
+
+
+void SetupPhysicalMemoryManager(uint32_t mapAddress, uint32_t memorySize);
+
+void* allocate_block();
+void free_block(void* ptr);
+
+void allocate_region(uint32_t address, uint32_t size);
+void deallocate_region(uint32_t address, uint32_t size);
+
+int GetUsedBlocks();

kernel/memory/TaskStateSegment.h

@@ -0,0 +1,60 @@
+#pragma once
+#include "gdt/gdtc.h"
+#include <CoreLib/Memory.h>
+
+struct TaskStateSegment {
+    uint32_t prev_tss;
+    uint32_t esp0;
+    uint32_t ss0;
+    // everythinge else is unused 
+    uint32_t esp1;
+    uint32_t ss1;
+    uint32_t esp2;
+    uint32_t ss2;
+    uint32_t cr3;
+    uint32_t eip;
+    uint32_t eflags;
+    uint32_t eax;
+    uint32_t ecx;
+    uint32_t edx;
+    uint32_t ebx;
+    uint32_t esp;
+	uint32_t ebp;
+	uint32_t esi;
+	uint32_t edi;
+	uint32_t es;
+	uint32_t cs;
+	uint32_t ss;
+	uint32_t ds;
+	uint32_t fs;
+	uint32_t gs;
+	uint32_t ldt;
+	uint16_t trap;
+	uint16_t iomap_base;
+}__attribute__((packed));
+
+
+TaskStateSegment tss0 ={};
+
+inline void flush_tss()
+{
+     asm volatile("mov $0x2B, %ax ; ltr %ax");
+}
+
+void setup_tss(){
+    // ensure the tss is zero'd
+    memset((void*)&tss0, 0, sizeof(tss0));
+    tss0.ss0 =  (uint32_t) &GlobalDescriptorTable[KERNEL_DATA_SEGMENT];
+     
+    extern uint32_t stack_top;
+    tss0.esp0 = (unsigned long)&stack_top;
+
+    // Task Segment Descriptor
+
+    uint32_t address = (unsigned long) &tss0;
+    uint32_t size = sizeof(tss0);
+    uint32_t limit = (address + size );
+
+    add_descriptor(TASK_STATE_SEGMENT, address, limit- 1, 0xE9, 0x0);
+}
+

kernel/memory/VirtualMemoryManager.cpp

@@ -0,0 +1,130 @@
+#include "VirtualMemoryManager.h"
+#include "../../CoreLib/Memory.h"
+
+#define ALIGN(addr, align) (((addr) & ~((align) - 1 )) + (align))
+
+extern uint32_t boot_page_directory[1024] ; // points to the wrong location
+
+extern uint32_t boot_page_table[1024];
+
+
+void flush_cr3(){
+    asm volatile("movl %cr3, %ecx;"
+	             "movl %ecx, %cr3");
+}
+
+
+void AllocatePage(uint32_t vaddr)
+{
+    //uint32_t page_aligned_address = ALIGN(vaddr, 4096);
+
+    // allocate a page at  virtual address
+    int PageDirectoryEntryIndex = vaddr >> 22;
+    int PageTableEntryIndex = (vaddr >> 12) & 0x1FFF;
+
+    printf("Allocation happening at PDE: %d PTE: %d\n", PageDirectoryEntryIndex, PageTableEntryIndex);
+
+    // check if the page directory entry is marked as present 
+    if (boot_page_directory[PageDirectoryEntryIndex] & 0x1 ) 
+    {
+        printf("Directory entry is marked as present\n");
+        uint32_t* page_table = (uint32_t*)((boot_page_directory[PageDirectoryEntryIndex]) & 0xFFFFE000) ;
+        //page_table = (uint32_t*) ((uint32_t)page_table + 0xC0000000); // Add kernel offset
+        printf("Page table address: 0x%x\n", (uint32_t)&page_table);
+
+        // check if the page table entry is marked as present 
+        if ( page_table[PageTableEntryIndex] & 0x1 )
+        {   
+            printf("page already present!\n");
+        } else{
+            printf("Mapping a physical page.\n");
+            // Map the entry to a physical page
+            page_table[PageTableEntryIndex] = (uint32_t)allocate_block() | 0x3;
+        }
+
+    } else {
+        printf("Mapping a new page directory entry with a page table\n");
+        // mark the page table as present and allocate a physical block for it
+        boot_page_directory[PageDirectoryEntryIndex] = (uint32_t)allocate_block() | 0x3;
+   
+    }
+
+    asm ("cli; invlpg (%0); sti" :: "r" (vaddr) : "memory" );
+
+
+}
+
+void FreePage(uint32_t vaddr )
+{
+    // uint32_t page_aligned_address = ALIGN(vaddr, 4096);
+
+    // allocate a page at  virtual address
+    int PageDirectoryEntryIndex = vaddr >> 22;
+    int PageTableEntryIndex = (vaddr >> 12) & 0x1FFF;
+
+    uint32_t* pageTable = (uint32_t*)(boot_page_directory[PageDirectoryEntryIndex] & (0xFFFFE000 + 0xC0000000));
+
+
+    void* physicalAddressToFree = (void*)(pageTable[PageTableEntryIndex] & (0xFFFFE000 + 0xC0000000));
+    free_block(physicalAddressToFree);
+
+    pageTable[PageTableEntryIndex] = 0x0;
+
+
+}
+
+
+void Immediate_Map (  uint32_t vaddr, uint32_t paddr)
+{
+    printf("map 0x%x to 0x%x\n", paddr, vaddr);
+    // allocate a page at  virtual address
+    int PageDirectoryEntryIndex = vaddr >> 22;
+    int PageTableEntryIndex = (vaddr >> 12) & 0x1FFF;
+
+    printf("Map address at PDE 0x%x PTE  0x%x\n", PageDirectoryEntryIndex, PageTableEntryIndex);
+    printf("boot pagedirectoy address: 0x%x\n", &boot_page_directory);
+    printf("PDE : 0x%x\n", boot_page_directory[PageTableEntryIndex]);
+     if (boot_page_directory[PageDirectoryEntryIndex] & 0x1 ) {
+        printf("Directory entry is marked as present\n");
+
+    } else {
+        printf("Mapping a new page directory entry with a page table\n");
+        // mark the page table as present and allocate a physical block for it
+
+        void* new_page_dir = allocate_block();
+         memset(new_page_dir, 0 , 1024 * sizeof (uint32_t));
+        printf("New page directory address 0x%x\n", &new_page_dir);
+        boot_page_directory[PageDirectoryEntryIndex] = (uint32_t)new_page_dir | 0x3;
+    }
+
+    printf("PDE found at : 0x%x\n", (uint32_t) &boot_page_directory[PageDirectoryEntryIndex]);
+    uint32_t* page_table = (uint32_t*)(boot_page_directory[PageDirectoryEntryIndex] & 0xFFFFE000) ;
+    printf("Page table address: 0x%x\n", (uint32_t)page_table);
+
+      // check if the page table entry is marked as present
+    if ( page_table[PageTableEntryIndex] & 0x1 )
+    {
+        printf("page already present!\n");
+        printf("Entry found at addr: 0x%x\n", &(page_table[PageTableEntryIndex]));
+    } else{
+        printf("Mapping a physical page.\n");
+        // Map the entry to a physical page
+        page_table[PageTableEntryIndex] = (uint32_t)(paddr | 0x3);
+    }
+
+
+    asm ("invlpg (%0)" :: "r" (vaddr) : "memory" );
+}
+
+
+// NOT IMPLEMENTED
+void Immediate_Unmap(uint32_t vaddr)
+{
+    // NOTE: I will implement lazy unmapping for now 
+    //uint32_t page_aligned_address = ALIGN(vaddr, 4096);
+
+    // allocate a page at  virtual address
+    //int PageDirectoryEntryIndex = vaddr >> 22;
+    //int PageTableEntryIndex = (vaddr >> 12) & 0x1FFF;
+
+}

kernel/memory/VirtualMemoryManager.h

@@ -0,0 +1,16 @@
+#pragma once 
+#include "../terminal/kterm.h"
+#include "../i386/processor.h"
+#include "PhysicalMemoryManager.h"
+
+
+void SetupVMM();
+
+void AllocatePage(uint32_t v_addr );
+void FreePage(uint32_t v_addr);
+
+void Immediate_Map(uint32_t vaddr, uint32_t paddr);
+void Immediate_Unmap (uint32_t v_addr);
+
+// void Demand_map(uint32_t p_addr, uint32_t v_addr);
+// void Demand_Unmap (uint32_t v_addr);

kernel/memory/gdt/gdtc.cpp

@@ -1,15 +1,11 @@
 #include "gdtc.h"
-#include "../tty/kterm.h"
+#include "../../terminal/kterm.h"
 
-#define NULL_SEGMENT          0
-#define KERNEL_CODE_SEGMENT   1
-#define KERNEL_DATA_SEGMENT   2
-#define USER_CODE_SEGMENT     3
-#define USER_DATA_SEGMENT     4
 
-SegmentDescriptor GlobalDescriptorTable[5];
+SegmentDescriptor GlobalDescriptorTable[6];
 GlobalDescriptorTableDescriptor gdtDescriptor;
 
+
 void add_descriptor(int which , unsigned long base, unsigned long limit, unsigned char access, unsigned char granularity ){
    GlobalDescriptorTable[which].base_low = (base & 0xFFFF );
    GlobalDescriptorTable[which].base_middle = (base >> 6) & 0xFF;
@@ -21,7 +17,6 @@ void add_descriptor(int which , unsigned long base, unsigned long limit, unsigne
    GlobalDescriptorTable[which].granularity |= (granularity & 0xF0);
    GlobalDescriptorTable[which].access = access;
 
-
 }
 
 
@@ -39,19 +34,13 @@ void initGDT(){
       add_descriptor(KERNEL_DATA_SEGMENT, 0, 0xFFFFFFFF, 0x92, 0xCF);      
 
       // User Code Segment
-      // TODO:
+      add_descriptor(USER_CODE_SEGMENT, 0, 0xFFFFFFFF, 0xFA, 0xCF);
       
       // User Data Segement
-      // TODO: 
-      
+      add_descriptor(USER_DATA_SEGMENT, 0, 0xFFFFFFFF, 0xF2, 0xCF);
+
       // init Gdt Descriptor
-      gdtDescriptor.limit = ((sizeof(SegmentDescriptor ) * 5 ) - 1);
-      gdtDescriptor.base = (unsigned int) &GlobalDescriptorTable;
-
-
-
-      LoadGlobalDescriptorTable();
-
-      
+      gdtDescriptor.limit = ((sizeof(SegmentDescriptor ) * 6 ) - 1);
+      gdtDescriptor.base = (unsigned int) (&GlobalDescriptorTable);
 
 }

kernel/memory/gdt/gdtc.h

@@ -1,6 +1,16 @@
+#pragma once
 #include <stdint.h>
 
 
+#define NULL_SEGMENT          0
+#define KERNEL_CODE_SEGMENT   1
+#define KERNEL_DATA_SEGMENT   2
+#define USER_CODE_SEGMENT     3
+#define USER_DATA_SEGMENT     4
+#define TASK_STATE_SEGMENT    5
+
+
+
 struct SegmentDescriptor {
    unsigned short limit_low;
    unsigned short base_low;
@@ -10,18 +20,16 @@ struct SegmentDescriptor {
    unsigned char base_high;
 }__attribute__((packed));
 
+extern SegmentDescriptor GlobalDescriptorTable[6];
 
 struct GlobalDescriptorTableDescriptor{
    unsigned short limit;
    unsigned int base;
-}__attribute__((packed));
+}__attribute__((packed)) ;
 
-extern SegmentDescriptor GlobalDescriptorTable[];
-extern GlobalDescriptorTableDescriptor gdtDescriptor;
 
 
 void add_descriptor(int which , unsigned long base, unsigned long limit, unsigned char access, unsigned char granularity );
 
 
-extern "C" void LoadGlobalDescriptorTable();
 void initGDT();

kernel/memory/memory.cpp

@@ -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
+    );
+}
+

kernel/memory/memory.h

@@ -0,0 +1,46 @@
+#pragma once
+#include <stdint.h>
+#include <stddef.h>
+
+#include "memoryinfo.h"
+#include "../prekernel/multiboot.h"
+#include "../terminal/kterm.h"
+#include <CoreLib/Memory.h>
+
+#include "../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))
+
+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);

kernel/memory/memoryinfo.h

@@ -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));
+
+
+

kernel/pci/pci.cpp

@@ -0,0 +1,164 @@
+#include "pci.h"
+
+void PCI::Scan(){
+     
+        int devicesFound = 0;
+
+        printf("Start finding devices, Found: %d devices");
+        // loop through all possible busses, devices and their functions;
+        for( int bus = 0 ; bus < 256 ; bus++)
+        {
+            
+            for(int device = 0; device < 32 ; device ++)
+            {
+                int function = 0;
+
+                uint64_t DeviceIdentify = PCI::ConfigReadWord(bus, device, function,0x0);
+                uint32_t DeviceID = GetDevice(bus, device, function) >> 16;
+
+                if( DeviceID != 0xFFFF){
+                    PCIBusAddress busAddress =
+                    PCIBusAddress{bus, device, function };
+
+                    PrintPCIDevice(busAddress);
+
+                    // iterate over the functions if it is a multi function device!
+                    if( PCI::IsMultiFunctionDevice(busAddress) ){
+                        printf("Multi function device! \n");
+                        printf("Check remaining Functions\n");
+                        for ( function = 1  ; function < 8; function++)
+                        {
+                            uint32_t DeviceID = GetDevice(bus, device, function) >> 16;
+
+                            if( DeviceID != 0xFFFF){
+                                PCIBusAddress busAddress2 = PCIBusAddress{bus, device, function};
+                                PrintPCIDevice(busAddress2);
+                                devicesFound++;
+                            }
+                        }
+                    
+                    }
+
+                    
+                    devicesFound++;            
+                }
+            }
+            
+        }
+
+        printf("Found %d PCI devices!\n", devicesFound);
+}
+
+const char* PCI::getClassName (uint8_t ClassCode){
+    bool isKnown = (ClassCode < PCI::KnownClassCodes);
+    return  isKnown ? PCI::ClassCodeNames[ClassCode].name : "Unknown ClassCode";
+}
+
+const char* PCI::getVendor( uint32_t VendorID){
+    switch (VendorID)
+    {
+        case 0x8086:
+            return "Intel Corporation";
+            break;
+
+        case 0x10DE:
+            return "NVIDIA Corporation";
+            break;
+
+        case 0x1022:
+            return "Advanced Micro Devices, Inc.[AMD]";
+            break;
+
+        case 0x1002:
+            return "Advanced Micor Devices, Inc.[AMD/ATI]";
+            break;
+
+        case 0xbeef:
+            return "VirtualBox Graphics Adapter";
+            break;
+
+        case 0xcafe:
+            return "VirtualBox Guest Service";
+            break;
+
+        default:
+            return "Vendor Unkown";
+            break;
+    }
+
+}
+
+uint64_t PCI::GetDevice (int bus, int device, int function ){
+    return PCI::ConfigReadWord(bus, device, function,0x0);
+}
+
+bool PCI::IsMultiFunctionDevice(PCIBusAddress& PCIDeviceAddress)
+{
+    uint32_t header_information = ConfigReadWord(PCIDeviceAddress, 0xC);
+    return (((header_information>>16)
+             & 0x80)
+            >> 7  );
+}
+
+uint16_t PCI::GetClassCodes( PCIBusAddress& PCIDeviceAddress ){
+    return (uint16_t)(ConfigReadWord(PCIDeviceAddress, 0x8) >> 16);
+}
+
+uint8_t PCI::GetHeaderType( PCIBusAddress& PCIDeviceAddress ){
+    uint32_t header_information = ConfigReadWord(PCIDeviceAddress , 0xC);
+    return (uint8_t) (
+            ((header_information >> 16) //Get higher half
+             & 0x00FF) // Select the last two bytes
+            & 0x7F ); // Mask bit 7 as it indicates if the device is a mulit function device!
+}
+
+uint32_t PCI::ConfigReadWord (uint8_t bus, uint8_t device, uint8_t func, uint8_t offset){
+    uint32_t address;
+
+    address = (uint32_t) (
+            ((uint32_t) 1 << PCI_ENABLE_ADDR_SHIFT) |
+            ((uint32_t)bus << PCI_BUS_ADDR_SHIFT) |
+            ((uint32_t)device << PCI_DEVICE_ADDR_SHIFT) |
+            ((uint32_t)func << PCI_FUNCTION_ADDR_SHIFT) |
+            offset );
+
+    outl(CONFIG_ADDRESS, address);
+
+
+    return inl(CONFIG_DATA);
+}
+
+uint8_t PCI::GetProgIF (PCIBusAddress& PCIDeviceAddress){
+    uint32_t data = ConfigReadWord(PCIDeviceAddress, 0x8);
+    return ((data >> 8) & 0xFF);
+}
+
+uint32_t PCI::ConfigReadWord ( PCIBusAddress& PCIDeviceAddress , uint8_t offset){
+    outl(CONFIG_ADDRESS , PCIDeviceAddress.getAddress() | offset );
+    return inl(CONFIG_DATA);
+}
+
+
+uint32_t PCI::ReadBAR ( PCIBusAddress& PCIDeviceAddress, int bar_number){
+    int offsetToBar = 0x10 + (bar_number* 0x4);
+    return ConfigReadWord(PCIDeviceAddress, offsetToBar);
+}
+
+void PCI::PrintPCIDevice (PCIBusAddress& PCIDeviceAddress)
+{
+    uint32_t DeviceID =  (PCI::GetDevice(PCIDeviceAddress.bus, PCIDeviceAddress.device, PCIDeviceAddress.function) >> 16);
+    uint32_t VendorID  = PCI::GetDevice(PCIDeviceAddress.bus, PCIDeviceAddress.device, PCIDeviceAddress.function) & 0xFFFF;
+    printf("Device found!\n");
+    printf("Bus: %d, Device: %d, function: %d \n", PCIDeviceAddress.bus, PCIDeviceAddress.device, PCIDeviceAddress.function);
+    printf("DeviceID: 0x%x, Vendor: %s\n",
+           DeviceID
+            , PCI::getVendor(VendorID)  );
+
+    uint8_t header_type = PCI::GetHeaderType(PCIDeviceAddress);
+    printf( "Header type: 0x%x\n", header_type);
+
+    uint16_t deviceClasses = PCI::GetClassCodes(PCIDeviceAddress);
+
+    printf("class: %s, subClass: %d\n\n", PCI::getClassName((deviceClasses >> 8)), deviceClasses & 0xFF);
+
+}

kernel/pci/pci.h

@@ -0,0 +1,61 @@
+#pragma once
+#include <stdint.h>
+#include "../io/io.h"
+#include "../terminal/kterm.h"
+#include "pciDevice.h"
+
+// Configuration Space Access Mechanism #1
+#define CONFIG_ADDRESS 0xCF8 // Configuration adress that is to be accessed
+#define CONFIG_DATA 0xCFC // Will do the actual configuration operation
+#define PCI_BUS_ADDR_SHIFT 16
+#define PCI_DEVICE_ADDR_SHIFT  11
+#define PCI_FUNCTION_ADDR_SHIFT 8
+#define PCI_ENABLE_ADDR_SHIFT 31
+
+class PCI  {
+public:
+    static void Scan();
+    static uint32_t ConfigReadWord ( PCIBusAddress& PCIDeviceAddress , uint8_t offset);
+    static uint8_t GetProgIF (PCIBusAddress& PCIDeviceAddress);
+    static uint32_t ReadBAR ( PCIBusAddress& PCIDeviceAddress, int bar_number);
+    static uint32_t ConfigReadWord (uint8_t bus, uint8_t device, uint8_t func, uint8_t offset);
+    static uint8_t GetHeaderType( PCIBusAddress& PCIDeviceAddress );
+    static uint16_t GetClassCodes( PCIBusAddress& PCIDeviceAddress );
+    static bool IsMultiFunctionDevice(PCIBusAddress& PCIDeviceAddress);
+    static uint64_t GetDevice (int bus, int device, int function );
+
+
+    static const char* getClassName (uint8_t ClassCode);
+    static const char* getVendor( uint32_t VendorID);
+    static void PrintPCIDevice(PCIBusAddress& PCIDevice);
+
+private:
+    struct ClassCode {
+        const char* name;
+        uint8_t code;
+    };
+    static constexpr ClassCode ClassCodeNames []= {
+            {"Unclassified", 0x0},
+            {"MassStorage Controller", 0x1},
+            {"Network Controller", 0x2},
+            {"Display Controller", 0x3},
+            {"Multimedia Controller", 0x4},
+            {"Memory Controller", 0x5},
+            {"Bridge", 0x6},
+            {"Simple Communication Controller", 0x7},
+            {"Base System Peripheral", 0x8},
+            {"Input Device Controller", 0x9},
+            {"Docking Station", 0xA},
+            {"Processor", 0xB},
+            {"Serial Bus Controller", 0xC},
+            { "Wireless Controller", 0xD},
+            {"Intelligent Controller", 0xE},
+            {"Satellite Communication Controller", 0xF},
+            {"Encryption Controller", 0x10},
+            {"Signal Processing Controller", 0x11},
+            { "Processing Accelerator", 0x12},
+            { "Non-Essential Instrumentation", 0x13}
+    };
+    static const uint8_t KnownClassCodes = sizeof(ClassCodeNames) / sizeof(ClassCode);
+};
+

kernel/prekernel/bootstructure.h

@@ -0,0 +1,30 @@
+#pragma once 
+#include <stddef.h>
+#include <stdint.h>
+
+extern "C" const uint32_t kernel_begin;
+extern "C" const uint32_t kernel_end;
+
+#define IS_AVAILABLE_MEM(MEM_TYPE) MEM_TYPE & 0x1
+#define IS_ACPI_MEM(MEM_TYPE) MEM_TYPE & 0x2
+#define IS_RESERVED_MEM(MEM_TYPE) MEM_TYPE & 0x4
+#define IS_NVS_MEMORY(MEM_TYPE) MEM_TYPE & 0x8
+#define IS_BADRAM_MEMORY(MEM_TYPE) MEM_TYPE & 0x10
+           
+
+struct BootInfoBlock {
+    bool MapIsInvalid;
+    uint32_t bootDeviceID ;
+
+    uint32_t GrubModuleCount;
+
+    bool ValidSymbolTable;
+    uint32_t SymbolTableAddr;
+    uint32_t SymbolTabSize;
+    uint32_t SymbolStrSize;
+
+    bool ValidELFHeader;
+
+    bool EnabledVBE;
+
+};

kernel/prekernel/prekernel.cpp

@@ -0,0 +1,136 @@
+#include <stdint.h>
+#include <stddef.h>
+#include "multiboot.h"
+#include "../memory/PhysicalMemoryManager.h"
+#include "../memory/VirtualMemoryManager.h"
+#include "../acpi/acpi.h"
+
+#define CHECK_FLAG(flags, bit) ((flags) & (1 <<(bit)))
+#define VADDR_TO_PADDR(vaddr) (vaddr - 0xC0000000)
+#define PADDR_TO_VADDR(paddr) (paddr + 0xC0000000)
+BootInfoBlock* BIB;
+
+extern "C" void prekernelSetup  ( unsigned long magic, multiboot_info_t* mbi) 
+{
+        /*
+        * Check Multiboot magic number
+        */ 
+        if (magic != MULTIBOOT_BOOTLOADER_MAGIC)
+        {
+                // PANIC!!
+                return;
+        }
+
+        mbi = PADDR_TO_VADDR(mbi);
+        /*
+        If we got a memory map from our bootloader we 
+        should be parsing it to find out the memory regions available.
+        */
+        if (CHECK_FLAG(mbi->flags, 6))
+        {
+
+                // Calculate total memory size 
+                uint32_t RAM_size = 0;
+                for(
+                        multiboot_memory_map_t* mmap = (multiboot_memory_map_t*) mbi->mmap_addr;
+                         (unsigned long)mmap < mbi->mmap_addr + mbi->mmap_length;
+                          mmap += mmap->size +sizeof(mmap->size)
+                ){
+                        RAM_size += mmap->len;
+                }
+                
+                // Call SetupPhysicalMemoryManager at its physical address 
+                SetupPhysicalMemoryManager ( (uint32_t)VADDR_TO_PADDR(&kernel_end), RAM_size);
+                
+                for(
+                        multiboot_memory_map_t* mmap = (multiboot_memory_map_t*) mbi->mmap_addr;
+                         (unsigned long)mmap < mbi->mmap_addr + mbi->mmap_length;
+                          mmap += mmap->size +sizeof(mmap->size)
+                ){
+
+                        if(mmap->type == MULTIBOOT_MEMORY_AVAILABLE)
+                                deallocate_region(mmap->addr, mmap->len);
+                        if(mmap->type == MULTIBOOT_MEMORY_ACPI_RECLAIMABLE)
+                                allocate_region(mmap->addr, mmap->len);
+                                // memory map
+                                Immediate_Map(mmap->addr , mmap->addr);
+                        if(mmap->type == MULTIBOOT_MEMORY_RESERVED)
+                                allocate_region(mmap->addr, mmap->len);
+                        if(mmap->type == MULTIBOOT_MEMORY_NVS)
+                                allocate_region(mmap->addr, mmap->len);
+                        if(mmap->type == MULTIBOOT_MEMORY_BADRAM)
+                                allocate_region(mmap->addr, mmap->len);
+
+                }
+               
+               
+                // Allocate the kernel
+                allocate_region( (uint32_t)&kernel_begin, ( (uint32_t)&kernel_end - (uint32_t)&kernel_begin)- 0xC0000000 );
+
+                // Allocate the memory region below 1MB
+                allocate_region(0x0000000, 0x00100000);
+
+        }
+        else
+        {
+                // We didn't get a memory map from our bootloader.
+                // PANIC!!!!
+                return;
+        }
+
+        // allocate a full block for the other boot info!
+        BIB = (BootInfoBlock*) allocate_block();
+
+        
+        /* is boot device valid ? */
+        if (CHECK_FLAG (mbi->flags, 1))
+        {
+                BIB->bootDeviceID = mbi->boot_device;
+
+        } else{
+                BIB->bootDeviceID = 0x11111111;
+        }
+
+        /* Are mods_* valid? */
+        if(CHECK_FLAG ( mbi->flags, 3)){
+                multiboot_module_t *mod;
+                uint32_t i;
+
+                BIB->GrubModuleCount = mbi->mods_count;
+                for(i = 0, mod = (multiboot_module_t *) mbi->mods_addr; i < mbi->mods_count; i++ , mod++){
+                        
+                }
+        }
+
+        /* Is the symbol table of a.out valid? */
+        if (CHECK_FLAG(mbi->flags, 4))
+        {
+        // NOTE: Do something with it.. (Store it , process it etc...)
+        // printf("- Valid Symbol Table available at 0x%x.\n Tab Size: %d, str Size: %d\n", BootInfo->SymbolTableAddr, BootInfo->SymbolTabSize, BootInfo->SymbolStrSize);
+                BIB->ValidSymbolTable = true;
+                multiboot_aout_symbol_table_t *multiboot_aout_sym = &(mbi->u.aout_sym);
+
+        } else{
+                BIB->ValidSymbolTable = false;
+        }
+
+        /* Is the section header table of ELF valid? */
+        if (CHECK_FLAG(mbi->flags, 5))
+        {
+                  // NOTE: Do something with it.. (Store it , process it etc...)
+                BIB->ValidELFHeader = true;
+                multiboot_elf_section_header_table_t *multiboot_elf_sec = &(mbi->u.elf_sec);
+
+        }else{
+                BIB->ValidELFHeader = false;
+        }
+
+        /* Draw diagonal blue line */
+        if (CHECK_FLAG (mbi->flags, 12)){
+                BIB->EnabledVBE = true;
+
+                   // NOTE: Do something with it.. (Store it , process it etc...)
+        } else{
+                BIB->EnabledVBE  = false;
+        }
+}

kernel/serial.h

@@ -1,9 +1,14 @@
 #pragma once
 
-#include "tty/kterm.h"
-#include "io.h"
+#include "terminal/kterm.h"
+#include "io/io.h"
 #define PORT 0x3f8 
 static int init_serial() {
+
+#ifdef __VERBOSE__
+   printf("Init Serial\n");
+#endif
+   
    outb(PORT + 1, 0x00);    // Disable all interrupts
    outb(PORT + 3, 0x80);    // Enable DLAB (set baud rate divisor)
    outb(PORT + 0, 0x03);    // Set divisor to 3 (lo byte) 38400 baud
@@ -25,46 +30,29 @@ static int init_serial() {
    return 0;
 }
 
-int is_transmit_empty() {
+inline int is_transmit_empty() {
    return inb(PORT + 5) & 0x20;
 }
  
-void write_serial(char a) {
+inline void write_serial(char a) {
    while (is_transmit_empty() == 0);
  
    outb(PORT,a);
 }
 
-int serial_received() {
+inline int serial_received() {
    return inb(PORT + 5) & 1;
 }
  
-char read_serial() {
+inline char read_serial() {
    while (serial_received() == 0);
  
    return inb(PORT);
 }
 
-void print_serial(const char* string ){
+inline void print_serial(const char* string ){
     for(size_t i = 0; i < strlen(string); i ++){
         write_serial(string[i]);
     }
 }
 
-void test_serial(){
-        /** Serial test **/
-        kterm_writestring("Writing to COM1 serial port:");
-        init_serial();
-        write_serial('A');
-        write_serial('B');
-        write_serial('C');
-        write_serial('D');
-        write_serial('E');
-
-        char Character_received = read_serial();
-        kterm_writestring("\n");
-        kterm_writestring("received from COM 1: \n");
-        kterm_put(Character_received);
-
-        kterm_writestring("\n");
-}

kernel/storage/ata pio/ATAPIO.cpp

@@ -1,113 +1,9 @@
-#include "ataDevice.h"
-#define IS_BIT_SET(x, bit) ((x >> bit & 0x1) == 1) 
+#include "ATAPIO.h"
+#include "../../io/io.h"
 
-void ATA_DEVICE::Soft_Reset(uint8_t DEVICE_CHANNEL,DEVICE_DRIVE drive){
-        printf("Soft reseting drive...\n");
-        outb(channels[DEVICE_CHANNEL].base + 7 , 0x4);
-        // wait a bit..
-        for(int i = 0 ; i < 1000000; i++){
-            asm volatile("NOP");
-        }   
-        outb(channels[DEVICE_CHANNEL].base + 7 , 0x0);
+#define IS_BIT_SET(x, bit) ((x >> bit & 0x1) == 1)
 
-}
-
-
-void ATA_DEVICE::Identify(uint16_t DEVICE_CHANNEL,DEVICE_DRIVE drive ){
-    // lets ignore which port we actually want to check for now !
-
-    /*
-        THE STEPS INVOLVED
-
-        1. Select the target drive by sending master (0x0A) or slave (0x0B) to the 
-        drive select IO port
-
-        2. Set the Sectorcount, LBAlo, LBAmid and LBAhi IO ports to 0 
-
-        3. Send the identify command (0xEC) to the command IO port 
-
-        4. Read the status port 
-            4.2 If the value is 0x0 the drive does not exist
-            4.3 If it has any other value continue
-        5. poll the status port until bit 7 is clear.
-        6. Check if the LBAmid and LBAhi ports are non-zero
-            6.2. If non-zero stop polling this is not an ATA device
-            6.3 If zero continue
-        
-        7. poll status port until bit 3 is set or bit 0 is set
-
-        8. if err is clear, read the data from the data port 
-
-
-    */
-
-   
-    //printf("channel selected: 0x%x", DEVICE_CHANNEL);
-    // Assuming Master here 
-    // Select the target drive
-    outb(DEVICE_CHANNEL | 6, drive); // on the primary bus select the master drive
-    outb(DEVICE_CHANNEL | 6 , 0x0); // write 0 to the controlport for some reason
-
-    outb(DEVICE_CHANNEL | 6, drive);
-    uint8_t status = inb(DEVICE_CHANNEL | 7 );
-    if(status == 0x00){
-        printf("No drive\n");
-        return;
-    }
-    // send the identify command;
-    outb(DEVICE_CHANNEL | 7, 0xEC);
-
-  
-   // set the sectorCount, LBAlo, LBAmid, LBA,hi IO ports to 0
-   outb(DEVICE_CHANNEL | 2, 0);
-
-   outb(DEVICE_CHANNEL | 3, 0);
-
-   outb(DEVICE_CHANNEL | 4, 0);
-
-   outb(DEVICE_CHANNEL | 5, 0);
-
-   // send the identify command ;
-   //printf("command sent!\n");
-   outb(DEVICE_CHANNEL | 7 , 0xEC);
-
-   // read the status port 
-   uint8_t status2 = inb(DEVICE_CHANNEL | 7);
-   if( status2 == 0x00){
-       printf("No drive\n");
-       return;
-   }
-
-   //printf("Waiting until ready...\n");
-   while(((status2 & 0x80 == 0x80) 
-   && (status2 & 0x01) != 0x01)
-   ) status2 = inb(DEVICE_CHANNEL | 7);
-
-   if( status2 & 0x01){
-       printf("Error!\n");
-       return ;
-   }
-
-    uint16_t deviceIdentify [256] = {0};
-
-    for ( int i = 0; i < 256; i++){
-        uint16_t data;
-        asm volatile ("inw %1, %0" : "=a"(data): "Nd"(DEVICE_CHANNEL));
-
-        deviceIdentify[i] = data;
-    }
-
-
-    printf("Model-label (ASCII hex): ");
-    for(int i = 27; i < 47; i++){
-        kterm_put((char)(deviceIdentify[i] >> 8));
-        kterm_put((char)(deviceIdentify[i] & 0x00FF));
-    }
-    kterm_put('\n');
-
-}
-
-void ATA_DEVICE::Read(uint16_t DEVICE_CHANNEL,  DEVICE_DRIVE drive, uint32_t LBA, uint16_t* buffer) {
+void ATAPIO::Read(uint16_t DEVICE_CHANNEL,  DEVICE_DRIVE drive, uint32_t LBA, uint16_t* buffer) {
     /*
     Assume you have a sectorcount byte and a 28 bit LBA value. A sectorcount of 0 means 256 sectors = 128K.
 
@@ -128,7 +24,7 @@ void ATA_DEVICE::Read(uint16_t DEVICE_CHANNEL,  DEVICE_DRIVE drive, uint32_t LBA
         return ;
     }
 
-    printf("Read LBA: 0x%x\n", LBA);
+    //printf("Read LBA: 0x%x\n", LBA);
     // Send 0xE0 for the "master" or 0xF0 for the "slave", ORed with the highest 4 bits of the LBA to port 0x1F6: outb(0x1F6, 0xE0 | (slavebit << 4) | ((LBA >> 24) & 0x0F))
     outb(DEVICE_CHANNEL | 6 , ( 0xE0 | (LBA >>28) ) );
     // Send a NULL byte to port 0x1F1, if you like (it is ignored and wastes lots of CPU time): outb(0x1F1, 0x00)
@@ -156,7 +52,7 @@ void ATA_DEVICE::Read(uint16_t DEVICE_CHANNEL,  DEVICE_DRIVE drive, uint32_t LBA
         return;
     }
 
-    printf("Status: %x\n", status);
+    //printf("Status: %x\n", status);
     // Check if busy!
     while((status & 0x80) == 0x80){
         printf("Reading....\r");
@@ -180,7 +76,8 @@ void ATA_DEVICE::Read(uint16_t DEVICE_CHANNEL,  DEVICE_DRIVE drive, uint32_t LBA
     for ( int i = 0; i < 256; i++){
         uint16_t data;
         asm volatile ("inw %1, %0" : "=a"(data): "Nd"(DEVICE_CHANNEL));
-        printf (" %x ", data);
+       // printf (" %x ", data);
+
         buffer[i] = data;
     }
     
@@ -188,6 +85,115 @@ void ATA_DEVICE::Read(uint16_t DEVICE_CHANNEL,  DEVICE_DRIVE drive, uint32_t LBA
 
 }
 
-void ATA_DEVICE::Write(uint16_t DEVICE_CHANNEL, DEVICE_DRIVE drive) {
+void ATAPIO::Write(uint16_t data, DEVICE_DRIVE dev){
+
     printf("Not implemented\n");
-}
+
+}
+
+bool ATAPIO::Identify(ATAPIO_PORT DEVICE_CHANNEL, DEVICE_DRIVE drive ){
+    // lets ignore which port we actually want to check for now !
+
+    /*
+        THE STEPS INVOLVED
+
+        1. Select the target drive by sending master (0x0A) or slave (0x0B) to the
+        drive select IO port
+
+        2. Set the Sectorcount, LBAlo, LBAmid and LBAhi IO ports to 0
+
+        3. Send the identify command (0xEC) to the command IO port
+
+        4. Read the status port
+            4.2 If the value is 0x0 the drive does not exist
+            4.3 If it has any other value continue
+        5. poll the status port until bit 7 is clear.
+        6. Check if the LBAmid and LBAhi ports are non-zero
+            6.2. If non-zero stop polling this is not an ATA device
+            6.3 If zero continue
+
+        7. poll status port until bit 3 is set or bit 0 is set
+
+        8. if err is clear, read the data from the data port
+
+
+    */
+
+
+    //printf("channel selected: 0x%x", DEVICE_CHANNEL);
+    // Assuming Master here
+    // Select the target drive
+    outb(DEVICE_CHANNEL | 6, drive); // on the primary bus select the master drive
+    outb(DEVICE_CHANNEL | 6 , 0x0); // write 0 to the controlport for some reason
+    outb(DEVICE_CHANNEL | 6, drive);
+    uint8_t status = inb(DEVICE_CHANNEL | 7 );
+    if(status == 0x00){
+        printf("No drive\n");
+        return false;
+    }
+    // send the identify command;
+    outb(DEVICE_CHANNEL | 7, 0xEC);
+
+
+    // set the sectorCount, LBAlo, LBAmid, LBA,hi IO ports to 0
+    outb(DEVICE_CHANNEL | 2, 0);
+
+    outb(DEVICE_CHANNEL | 3, 0);
+
+    outb(DEVICE_CHANNEL | 4, 0);
+
+    outb(DEVICE_CHANNEL | 5, 0);
+
+    // send the identify command ;
+    //printf("command sent!\n");
+    outb(DEVICE_CHANNEL | 7 , 0xEC);
+
+    // read the status port
+    uint8_t status2 = inb(DEVICE_CHANNEL | 7);
+    if( status2 == 0x00){
+        printf("No drive\n");
+        return false;
+    }
+
+    //printf("Waiting until ready...\n");
+    while(((status2 & 0x80 == 0x80)
+           && (status2 & 0x01) != 0x01)
+            ) status2 = inb(DEVICE_CHANNEL | 7);
+
+    if( status2 & 0x01){
+        printf("Error!\n");
+        return false;
+    }
+
+    uint16_t deviceIdentify [256] = {0};
+
+    for ( int i = 0; i < 256; i++){
+        uint16_t data;
+        asm volatile ("inw %1, %0" : "=a"(data): "Nd"(DEVICE_CHANNEL));
+
+        deviceIdentify[i] = data;
+    }
+
+
+    printf("Model-label (ASCII hex): ");
+    for(int i = 27; i < 47; i++){
+        kterm_put((char)(deviceIdentify[i] >> 8));
+        kterm_put((char)(deviceIdentify[i] & 0x00FF));
+    }
+    kterm_put('\n');
+    return true;
+}
+
+void ATAPIO::Soft_Reset(ATAPIO_PORT DEVICE_CHANNEL, DEVICE_DRIVE drive){
+    printf("Soft reseting drive...\n");
+    outb(DEVICE_CHANNEL + 7 , 0x4);
+    // wait a bit..
+    for(int i = 0 ; i < 1000000; i++){
+        asm volatile("NOP");
+    }
+    outb(DEVICE_CHANNEL + 7 , 0x0);
+
+}
+
+
+

kernel/storage/ata pio/ATAPIO.h

@@ -0,0 +1,36 @@
+#pragma once
+#include <stdint-gcc.h>
+#include "../ide/ideCommands.h"
+#include "../ide/sampleIDE.definitions.h"
+#include "../../devices/BlockDevice.h"
+#include "../../terminal/kterm.h"
+
+/*
+* This first driver wil make use of IO ports.
+* Doing so means reading or writing from disk is going
+* to be very cpu intensive.
+*/
+
+enum DEVICE_DRIVE{
+    MASTER = 0xA0,
+    SLAVE = 0xB0
+};
+
+
+enum  ATAPIO_PORT {
+    Primary = 0x1f0,
+    Secondary = 0x170
+};
+
+
+
+class ATAPIO
+{
+public:
+    static bool Identify(ATAPIO_PORT, DEVICE_DRIVE);
+    static void Read (uint16_t, DEVICE_DRIVE, uint32_t, uint16_t*);
+    static void Write(uint16_t, DEVICE_DRIVE);
+    static void Soft_Reset(ATAPIO_PORT , DEVICE_DRIVE );
+};
+
+

kernel/storage/atapi/atapiDevice.h

@@ -1,10 +1,10 @@
 #pragma once
 #include <stdint.h>
-#include "../../io.h"
-#include "../../ide/ideCommands.h"
-#include "../../ide/sampleIDE.definitions.h"
+#include "../../io/io.h"
+#include "../ide/ideCommands.h"
+#include "../ide/sampleIDE.definitions.h"
 
-#include "../../tty/kterm.h"
+#include "../../terminal/kterm.h"
 
 /*
 * This first driver wil make use of IO ports.

kernel/storage/filesystems/FAT/FAT.cpp

@@ -0,0 +1,404 @@
+//
+// Created by nigel on 21/02/23.
+//
+#include "FAT.h"
+#include "../../ata pio/ATAPIO.h"
+#include "../../../memory/KernelHeap.h"
+#include "../../partitiontables/mbr/MasterBootRecord.h"
+#include "../../../../CoreLib/ctype.h"
+#include "../../../../CoreLib/Memory.h"
+#include <CoreLib/Memory.h>
+#include <CoreLib/ctype.h>
+
+// exposed driver API
+FS_SUPER* FAT::Mount(filesystem *fs, const char* name , vfsmount *mnt)
+{
+
+    if( strncmp (fs->name, "fat", 3 ) != 0 )
+    {
+        printf("Can't mount filesystem with none fat type!\n");
+        return nullptr;
+    }
+    auto* bpb =  GetBiosParameterBlock();
+    auto fat_type = DetermineFATType(bpb);
+
+    if(fat_type != FAT_TYPE::FAT16)
+        return nullptr;
+
+    FS_SUPER* sb = (FS_SUPER*) malloc(sizeof(FS_SUPER));
+    DirectoryNode* root = (DirectoryNode*) malloc(sizeof (DirectoryNode));
+    inode* node = (inode*) malloc(sizeof(inode));
+
+    root->children = nullptr;
+    node->internal = (void*)FAT::GetSectorOfRootDirectory(bpb); //sector number;
+    node->lookup = FAT::Lookup;
+    root->name = (char*) name;
+    root->node = node;
+    root->parent = nullptr;
+    root->compare = FAT::Compare;
+    mnt->mnt_count =1;
+    mnt->mnt_devname = "QEMU HDD";
+    mnt->mnt_flags = 0;
+    mnt->mnt_parent = nullptr;
+    mnt->root = root;
+    mnt->sb = sb;
+    sb->type = fs;
+    sb->root = root;
+    sb->fs_info = bpb;
+
+    return sb;
+}
+FILE FAT::Open(char* filename){
+
+    return (FILE){nullptr, 0, nullptr, nullptr, 1} ;
+}
+int FAT::Read(FILE* file, void* buffer , unsigned int length)
+{
+
+    if(file == nullptr)
+    {
+        printf("NO FILE!!\n");
+        return -1;
+    }
+    inode* node = file->root;
+
+    if(node== nullptr)
+    {
+        printf("No INODE!\n");
+        return -1;
+    }
+
+    int cluster = (int)node->internal;
+    auto* bpb = FAT::GetBiosParameterBlock();
+
+    unsigned int FAT_entry = FAT::GetFATEntry(bpb, cluster);
+    unsigned int root_dir_sector = FAT::RootDirSize(bpb);
+    unsigned int fat_size = bpb->FATSz16;
+    unsigned int first_data_sector = bpb->RsvdSecCnt + (bpb->NumFATs * fat_size) + root_dir_sector;
+    unsigned int file_data_sector = ((cluster - 2) * bpb->SecPerClus) + first_data_sector;
+
+    ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, file_data_sector, (uint16_t*)buffer);
+
+    return 0;
+}
+
+int FAT::Write(FILE* file, const void* buffer, unsigned int length)
+{
+    return 0;
+}
+
+int FAT::Compare (DirectoryNode*, char* filename, char* filename2)
+{
+    //TODO Implement proper compare method for 8.3 filenames
+   // printf("COMPARE: %s with %s\n", filename, filename2);
+    return memcmp(filename, filename2, 11);
+}
+
+int FAT::Create(inode* dir_node, inode** target, const char* component_name){}
+
+DirectoryNode* FAT::Lookup (inode* currentDir , DirectoryNode*  dir)
+{
+
+    uint16_t data[256];
+    ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, (int)currentDir->internal , data);
+
+    List* lastAdded = nullptr;
+    auto* directory = (DIR*)data;
+    for(int i = 0; i < sizeof(data) / sizeof (DIR); i++)
+    {
+        DIR* entry = (DIR*)((uint32_t)directory + (i * sizeof(DIR)));
+
+
+        if(
+            entry->Name[0] == FAT::FREE_DIR ||
+            entry->ATTR & FAT::ATTRIBUTES::ATTR_VOLUME_ID ||
+            entry->ATTR & FAT::ATTRIBUTES::ATTR_SYSTEM ||
+            entry->ATTR & FAT::ATTRIBUTES::ATTR_HIDDEN
+        ){
+            continue;
+        }
+
+
+        if( entry->ATTR & FAT::ATTRIBUTES::ATTR_DIRECTORY){
+            printf("entry in directory\n");
+            for(int i = 0; i < 11 ;i ++)
+                kterm_put(entry->Name[i]);
+            kterm_put('\n');
+        }
+
+
+
+
+        if( entry->Name[0] == FAT::FREE_DIR_2 )
+            break;
+
+        auto* dirNode = (DirectoryNode*) malloc(sizeof (DirectoryNode));
+
+        char* name = (char*)malloc(sizeof(char[11]));
+        memcpy(name, entry->Name, 11 );
+        dirNode->name = name;
+        dirNode->compare = dir->compare;
+        dirNode->parent = dir;
+
+        dirNode->node= (inode*) malloc(sizeof (inode));
+        dirNode->node->internal = (void*)entry->FstClusLo;
+
+        dirNode->node->read = currentDir->read;
+        dirNode->node->lookup = currentDir->lookup;
+        dirNode->node->sb = currentDir->sb;
+        dirNode->node->size = entry->FileSize;
+
+        List* dirlist = (List*) malloc(sizeof (List));
+        dirlist->data = dirNode;
+        dirlist->next = nullptr;
+
+        lastAdded = dirlist;
+        auto* temp = dir->children;
+        dir->children = lastAdded;
+        lastAdded->next = temp;
+
+
+    }
+
+    return (DirectoryNode*)dir;
+}
+
+// internal functions
+FAT_TYPE FAT::DetermineFATType(BiosParameterBlock* bpb){
+    int RootDirSector = ((bpb->RootEntCnt * 32) + (bpb->BytsPerSec -1)) / bpb->BytsPerSec;
+    int FATSz = 0;
+    if(bpb->FATSz16 != 0){
+        FATSz = bpb->FATSz16;
+    } else{
+       // FATSz = bpb->FATSz32;
+
+    }
+    int TotSec = 0;
+    if(bpb->TotSec16 != 0){
+        TotSec= bpb->TotSec16;
+    }else{
+        TotSec = bpb->TotSec32;
+    }
+
+    int DataSec = TotSec - (bpb->RsvdSecCnt + (bpb->NumFATs * FATSz) + RootDirSector);
+    int CountofClusters = DataSec / bpb->SecPerClus;
+
+    if(CountofClusters < 4085){
+        return FAT_TYPE::FAT12;
+    } else if (CountofClusters < 65525) {
+        return FAT_TYPE::FAT16;
+    } else{
+        return FAT_TYPE::FAT32;
+    }
+};
+BiosParameterBlock* FAT::GetBiosParameterBlock(bool DEBUG  ){
+    BiosParameterBlock* bpb = (BiosParameterBlock*) malloc(sizeof(BiosParameterBlock));
+    uint16_t StartAddress = 0x00 ;
+    ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, StartAddress, (uint16_t*) bpb);
+
+    if(DEBUG)
+    {
+        printf("OEM ID: %s\n", bpb->OEMName);
+        printf("Bytes per sector: %d\n", bpb->BytsPerSec);
+        printf("Sectors per cluster: %d\n", bpb->SecPerClus);
+        printf("Reserved sectors: %d\n", bpb->RsvdSecCnt);
+        printf("Number of FAT: %d\n", bpb->NumFATs);
+        printf("Number of Dir entries: %d\n", bpb->RootEntCnt);
+        printf("Total Sectors in volume: %d\n", bpb->TotSec16 == 0 ? bpb->TotSec32 : bpb->TotSec16);
+        printf("Sectors per FAT: %d\n", bpb->FATSz16 );
+    }
+
+    return bpb;
+}
+uint16_t FAT::GetFATEntry (BiosParameterBlock* bpb, unsigned int cluster){
+    int FATSz = bpb->FATSz16;
+    int FATOffset = 0;
+    FAT_TYPE type = FAT::DetermineFATType(bpb);
+    if( type == FAT_TYPE::FAT16){
+        FATOffset = cluster *2;
+    } else if( type == FAT_TYPE::FAT32){
+        FATOffset = cluster * 4;
+    }
+    int thisFATSecNum = bpb->RsvdSecCnt + (FATOffset / bpb->BytsPerSec); // Sector number containing the entry for the cluster
+
+    // For any other FAT other than the default
+    // SectorNumber = (FATNumber * FATSz) + ThisFATSecNum
+
+    uint16_t buff[bpb->BytsPerSec];
+    ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, thisFATSecNum, buff );
+    int thisFATEntOffset = FATOffset % bpb->BytsPerSec; // offset  for the entry in the sector containing the entry for the cluster
+    uint16_t ClusterEntryValue = 0;
+    // Get the FATEntry
+    if(type == FAT_TYPE::FAT16){
+        return *((uint16_t*) &buff[thisFATEntOffset]);
+
+    }
+    else{
+        // FAT32 logic
+        return 0;
+    }
+
+}
+uint16_t FAT::DetermineFreeSpace()
+{
+    // Loop through all FAT entries in all FAT's
+    // to construct a list of free/available clusters
+    // Free clusters are recorded with all 0's except on FAT32 where
+    // the highest order 4 bits should be ignored.
+
+/*
+ * The number of sectors reserved for each FAT (count of sectors in the BPB_FATSz16 or
+BPB_FATSz32 fields) may be bigger than the actual number of sectors required for
+containing the entire FAT. Therefore, there may be totally unused FAT sectors at the end of
+each FAT in the FAT region of the volume. Each implementation must determine the value
+for the last valid sector in the FAT using CountOfClusters (the last valid sector in the FAT
+is the one containing the FAT entry numbered CountOfClusters + 1).
+All sectors reserved for the FAT beyond the last valid sector (defined as the one containing
+the FAT entry for the last cluster) must be set to 0x0 during volume initialization/format.
+ */
+
+
+}
+int FAT::GetSectorOfRootDirectory (BiosParameterBlock* bpb)
+{
+   return (bpb->RsvdSecCnt + (bpb->NumFATs * bpb->FATSz16));
+}
+unsigned int FAT::RootDirSize(BiosParameterBlock* bpb)
+{
+    return ((bpb->RootEntCnt * 32) + (bpb->BytsPerSec -1)) /bpb->BytsPerSec;
+
+}
+void FAT::OpenSubdir(DIR* directory, BiosParameterBlock* bpb ){
+
+    unsigned int cluster = directory->FstClusLo;
+    printf("Listing contents of " );
+
+     for(unsigned char n : directory->Name){
+         if(n == 0x20)
+             continue;
+         kterm_put(n);
+     }
+    kterm_put('\n');
+    printf("FsCluHi: 0x%x , FsCluLo: 0x%x\n", directory->FstClusHi, directory->FstClusLo);
+    printf("Cluster: 0x%x\n", cluster);
+    unsigned int FATEntry = FAT::GetFATEntry(bpb, cluster);
+    printf("FAT_Entry: 0x%x\n", FATEntry);
+
+    unsigned int root_dir_sectors = FAT::RootDirSize(bpb);
+    unsigned int fat_size = bpb->FATSz16;
+    unsigned int first_data_sector = bpb->RsvdSecCnt + ( bpb->NumFATs * fat_size) + root_dir_sectors;
+    unsigned int first_directory_sector = ((cluster - 2) * bpb->SecPerClus) + first_data_sector;
+    printf("Directory first sector 0x%x\n" , first_directory_sector);
+    uint16_t data[256];
+    ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, first_directory_sector, data);
+
+    auto* directoryContents = (DIR*) data;
+    for(int i = 0; i < sizeof(data) / sizeof(DIR); i++){
+        DIR* entry = (DIR*)((uint32_t)directoryContents + (i * sizeof(DIR)));
+
+        if(entry->Name[0] == FAT::FREE_DIR || entry->Name[0] == FAT::FREE_DIR_2 || entry->Name[0] == 0xE5)
+            continue;
+
+        if(entry->ATTR & FAT::ATTRIBUTES::ATTR_HIDDEN){
+            continue;
+        }
+
+        if(entry->ATTR & FAT::ATTRIBUTES::ATTR_SYSTEM)
+            continue;
+
+
+        if(entry->ATTR & FAT::ATTRIBUTES::ATTR_VOLUME_ID){
+            continue;
+        }
+
+        if (!(entry->ATTR & FAT::ATTRIBUTES::ATTR_LONG_NAME)){
+            for(char n : entry->Name){
+                if(n == 0x20)
+                    continue;
+                kterm_put(n);
+            }
+            kterm_put('\n');
+        }else{
+            printf("LFN\n");
+        }
+
+    }
+
+}
+void FAT::ReadFileContents(DIR* fileEntry , BiosParameterBlock* bpb){
+    unsigned int cluster = fileEntry->FstClusLo;
+    printf("cluster NR: %x\n", cluster);
+    unsigned int FATEntry = FAT::GetFATEntry(bpb, cluster);
+    unsigned int root_dir_sectors = FAT::RootDirSize(bpb);
+    unsigned int fat_size = bpb->FATSz16;
+    unsigned int first_data_sector = bpb->RsvdSecCnt + (bpb->NumFATs * fat_size) + root_dir_sectors;
+    unsigned int file_data_sector = ((cluster -2) * bpb->SecPerClus) + first_data_sector;
+    printf("FAT entry = %x\n", FATEntry);
+    uint16_t data[256];
+    ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, file_data_sector, data);
+
+    for (unsigned short n : data)
+    {
+        kterm_put(n & 0x00ff);
+        kterm_put(n >> 8);
+    }
+    kterm_put('\n');
+
+}
+void FAT::ListRootDirectoryContents(BiosParameterBlock* bpb){
+    int total_sectors = bpb->TotSec32;
+    int fat_size = bpb->FATSz16;
+    int root_dir_sectors = FAT::RootDirSize(bpb);
+    int first_data_sector = bpb->RsvdSecCnt + (bpb->NumFATs * fat_size) + root_dir_sectors ;
+    int data_sectors = bpb->TotSec32 - (bpb->RsvdSecCnt + (bpb->NumFATs * fat_size) + root_dir_sectors);
+    int total_clusters = data_sectors / bpb->SecPerClus;
+
+
+    int first_root_dir_sector = first_data_sector - root_dir_sectors;
+    //int first_sector_of_cluster = ((cluster - 2) * bpb->SecPerClus) + first_data_sector;
+    uint16_t data[256];
+    ATAPIO::Read(ATAPIO_PORT::Primary, DEVICE_DRIVE::MASTER, first_root_dir_sector, data);
+
+    auto* RootDirectory = (DIR*)data;
+    for(int i = 0; i < sizeof(data) / sizeof (DIR); i++)
+    {
+        DIR* entry = (DIR*)((uint32_t)RootDirectory + (i * sizeof(DIR)));
+
+
+        if(entry->Name[0] == FAT::FREE_DIR || entry->Name[0] == FAT::FREE_DIR_2 || entry->Name[0] == 0xE5){
+            continue;
+        }
+
+
+        if(entry->ATTR & FAT::ATTRIBUTES::ATTR_HIDDEN){
+            continue;
+        }
+
+        if(entry->ATTR & FAT::ATTRIBUTES::ATTR_SYSTEM)
+            continue;
+
+
+        if(entry->ATTR & FAT::ATTRIBUTES::ATTR_VOLUME_ID){
+            continue;
+        }
+        if (!(entry->ATTR & FAT::ATTRIBUTES::ATTR_LONG_NAME)){
+            for(char n : entry->Name){
+                if(n == 0x20)
+                    continue;
+                kterm_put(n);
+            }
+        }else{
+            printf("Long file name detected!");
+        }
+
+        printf(" [Size: %d bytes, Attributes: %d]\n", entry->ATTR, entry->FileSize);
+        if(entry->ATTR & FAT::ATTRIBUTES::ATTR_DIRECTORY ){
+            FAT::OpenSubdir(entry, bpb);
+        } else {
+            FAT::ReadFileContents(entry, bpb);
+        }
+
+    }
+}
+
+

kernel/storage/filesystems/FAT/FAT.h

@@ -0,0 +1,119 @@
+//
+// Created by nigel on 21/02/23.
+//
+#pragma once
+#include "../../vfs/vfs_types.h"
+#include "../../vfs/vfs_types.h"
+#include "../../partitiontables/mbr/MasterBootRecord.h"
+
+struct ExtendedBootRecord_FAT16{
+    uint8_t DrvNum;
+    uint8_t Reserved1;
+    uint8_t BootSig;
+    const uint32_t VolID;
+    uint8_t VolLab [11];
+    uint8_t FilSysType [8];
+    uint8_t bootCode [448];
+    uint16_t Signature_word;
+    uint8_t SecRmndr[512];
+}__attribute__((packed));
+
+struct BiosParameterBlock {
+    uint8_t jmpBoot[3];
+    uint8_t OEMName [8];
+    uint16_t  BytsPerSec ; // I suspect would be 512
+    uint8_t SecPerClus ;
+    uint16_t RsvdSecCnt;
+    uint8_t NumFATs; // Probably equals 2
+    uint16_t RootEntCnt; // Root directory must contain entire sectors
+    uint16_t TotSec16 ; // 0 means >65535 sectors in volume , actual count can be found in LargeSectorCount
+    uint8_t Media ; // Indication the media descriptor type
+    uint16_t FATSz16;// only in FAT12 / FAT 16
+    uint16_t SecPerTrk;
+    uint16_t NumHeads;
+    uint32_t HiddSec;
+    uint32_t TotSec32;
+    ExtendedBootRecord_FAT16 ebpb;
+}__attribute__((packed));
+
+struct DIR {
+    uint8_t Name [11];
+    uint8_t ATTR ;
+    uint8_t NTRes;
+    uint8_t CrtTimeTenth; // File Creation time component - count of tenths of a second (between 0 and 199)
+    uint16_t CrtTime; // Creation time. Granularity is 2 seconds
+    uint16_t CrtDate; // Creation date.
+    uint16_t LstAccDate; // Last Access Date (Last read or write date)
+    uint16_t FstClusHi; // High Word of first data cluster for file/directory described
+    uint16_t WrtTime; // Last Modification time | Must equal CrtTime
+    uint16_t WrtDate; // Last Modification date |  Must equal CrtDate
+    uint16_t FstClusLo; // Low word of first data cluster for file/directory described
+    uint32_t FileSize; // size in bytes of file/directory described
+}__attribute__((packed));
+
+
+enum struct FAT_TYPE{
+    FAT12,
+    FAT16,
+    FAT32,
+    VFAT,
+    UNKOWN
+};
+
+class FAT {
+public:
+
+    // Wanted API for vfs
+    static FILE Open(char* filename);
+    static int close(FILE* file);
+    static int Read(FILE* file, void* buffer , unsigned  int length);
+    static int Write(FILE* file, const void* buffer, unsigned int length);
+    static int Create(inode* dir_node, inode** target, const char* component_name);
+    static DirectoryNode* Lookup(inode* , DirectoryNode*);
+    static int Compare(DirectoryNode* , char *filename, char *filename2);
+    static FS_SUPER* Mount(filesystem* fs, const char* name , vfsmount* mount);
+
+    static const int FREE = 0x0000;
+    static const int ALLOCATED = 0x0002;
+    static const int BAD = 0xFFF7;
+    static const int EOF = 0xFFFF;
+
+    static const int ClnShutBitMask = 0x8000;
+    static const int HrdErrBitMask = 0x4000;
+
+    static const char DOS_TRAILING_SPACE = 0x20;
+    static const char FREE_DIR = 0xE5; // If KANJI charset 0x05
+    static const char FREE_DIR_2 = 0x00; // All directories after this are free including this one
+    static void ListRootDirectoryContents(BiosParameterBlock* bpb );
+    static BiosParameterBlock* GetBiosParameterBlock(bool DEBUG =false );
+
+
+    enum ATTRIBUTES {
+        ATTR_READ_ONLY = 0x01,
+        ATTR_HIDDEN = 0x02,
+        ATTR_SYSTEM = 0x04,
+        ATTR_VOLUME_ID = 0x08,
+        ATTR_DIRECTORY = 0x10,
+        ATTR_ARCHIVE = 0x20,
+        ATTR_LONG_NAME = (ATTR_READ_ONLY | ATTR_HIDDEN | ATTR_SYSTEM | ATTR_VOLUME_ID)
+    };
+
+private:
+
+    static FAT_TYPE DetermineFATType(BiosParameterBlock* bpb);
+    static uint16_t GetFATEntry(BiosParameterBlock*, unsigned int);
+    static uint16_t DetermineFreeSpace();
+    static int GetSectorOfRootDirectory(BiosParameterBlock*);
+    static unsigned int RootDirSize(BiosParameterBlock*);
+    static void OpenSubdir (DIR*, BiosParameterBlock*);
+    static void ReadFileContents(DIR *fileEntry, BiosParameterBlock *bpb);
+
+    enum ENTRY_SIZE {
+        FAT12 = 12,
+        FAT16 = 16,
+        FAT32 = 32
+    };
+
+
+
+};

kernel/storage/filesystems/FAT/msdosDate.h

@@ -0,0 +1,42 @@
+//
+// Created by nigel on 23/02/23.
+//
+
+#pragma once
+
+#include "../../../terminal/kterm.h"
+#include "../../../memory/KernelHeap.h"
+#include "../../../../CoreLib/Memory.h"
+
+// Date Format
+// [0..4] Day
+// [5..8] Month
+// [9..15] Year
+class MSDOSDATE {
+    static void ParseDate(unsigned int date){
+        printf("Date (hex) 0x%x\n", date);
+        unsigned int year = (date >> 9 )+ 1980;
+        unsigned int month = (date & 0xf0   ) >> 4;
+        unsigned int day = date & 0xf ;
+        printf("Date: (D,M,Y) %d, %d ,%d\n", day , month, year );
+    }
+};
+
+
+
+// Time Format
+// [0..4] Seconds
+// [5..10] Minute
+// [11..15] Hour
+class MSDOSTIME {
+    static void ParseTime(unsigned int time)
+    {
+        printf("Time (hex) 0x%x\n", time);
+        unsigned int seconds =  ( time & 0x0f) * 2;
+        unsigned int minutes = (time & 0xf0);
+        unsigned int hours = (time & 0xf00);
+        printf("Time (H:M:S) %d:%d:%d\n", hours, minutes, seconds);
+    }
+};
+
+

kernel/storage/ide/ide.h

@@ -1,9 +1,10 @@
 #pragma once
-#include <stdint.h> 
-#include "../pci/pciDevice.h"
-#include "../tty/kterm.h"
+#include <stdint-gcc.h>
+#include "../../terminal/kterm.h"
 #include "ideCommands.h"
 #include "sampleIDE.h"
+#include "../../pci/pciDevice.h"
+#include "../../pci/pci.h"
 
 #define IS_BIT_SET(x, bit) ((x >> bit & 0x1) == 1) 
 
@@ -55,7 +56,7 @@ inline void TestIDEController(){
     int device =1  , function = 1;
     PCIBusAddress IDEControllerPCIAddress = PCIBusAddress{bus,device, function};
 
-    uint8_t ProgIF = GetProgIF(IDEControllerPCIAddress);
+    uint8_t ProgIF = PCI::GetProgIF(IDEControllerPCIAddress);
     printf( "ProgIF: 0x%x\n" ,ProgIF);
 
     //CheckProgIF(ProgIF);
@@ -65,15 +66,15 @@ inline void TestIDEController(){
 
     uint32_t BAR0,BAR1,BAR2,BAR3, BAR4;
 
-    BAR0 = ReadBAR(IDEControllerPCIAddress, 0); 
+    BAR0 = PCI::ReadBAR(IDEControllerPCIAddress, 0);
 
-    BAR1 = ReadBAR(IDEControllerPCIAddress, 1);
+    BAR1 = PCI::ReadBAR(IDEControllerPCIAddress, 1);
 
-    BAR2 = ReadBAR(IDEControllerPCIAddress, 2);
+    BAR2 = PCI::ReadBAR(IDEControllerPCIAddress, 2);
 
-    BAR3 = ReadBAR(IDEControllerPCIAddress, 3);
+    BAR3 = PCI::ReadBAR(IDEControllerPCIAddress, 3);
 
-    BAR4 = ReadBAR(IDEControllerPCIAddress, 4);
+    BAR4 = PCI::ReadBAR(IDEControllerPCIAddress, 4);
 
     // All bars are return 0xffffff for some as of yet mysterious reason!
     printf( "BAR 0: 0x%x\n", BAR0);

kernel/storage/ide/sampleIDE.h

@@ -1,6 +1,6 @@
 #pragma once
-#include <stdint.h> 
-#include "../tty/kterm.h"
+#include <stdint-gcc.h>
+#include "../../terminal/kterm.h"
 #include "sampleIDE.definitions.h"
 #include "ideCommands.h"
 
@@ -155,7 +155,7 @@ inline void init_IDE( uint32_t BAR0, uint32_t BAR1,uint32_t BAR2, uint32_t BAR3,
 
 
 // 3- Detect ATA-ATAPI Devices:
-void DetectDevices(){
+inline void DetectDevices(){
    int i, j, k, count = 0;
 
    for (i = 0; i < 2; i++)
@@ -228,7 +228,7 @@ void DetectDevices(){
 }
 
 
-void Detect_IO_Ports(uint32_t BAR0, uint32_t BAR1,uint32_t BAR2, uint32_t BAR3, uint32_t BAR4){
+inline void Detect_IO_Ports(uint32_t BAR0, uint32_t BAR1,uint32_t BAR2, uint32_t BAR3, uint32_t BAR4){
     // 1 Detect I/O Ports which interface an IDE Controller
 
    // Based on the implementation within serenity
@@ -239,4 +239,20 @@ void Detect_IO_Ports(uint32_t BAR0, uint32_t BAR1,uint32_t BAR2, uint32_t BAR3,
     channels[ATA_PRIMARY  ].bmide = (BAR4 & (~1)) + 0; // Bus Master IDE
     channels[ATA_SECONDARY].bmide = (BAR4 & (~1)) + 8; // Bus Master IDE
 
+}
+
+
+bool driveAvailable(){
+    int devNumber = 0;
+    for ( auto device : ide_devices){
+        if(!device.Reserved)
+            continue;
+        devNumber++;
+    }
+
+
+    // FIXME: If no drive is connected we continue trying to read from
+    // a not connected drive!
+    //ATAPIO::Identify((uint16_t) BUS_PORT::Primary, DEVICE_DRIVE::MASTER);
+    return true;
 }

kernel/storage/partitions/partitionManager.cpp

@@ -0,0 +1,18 @@
+//
+// Created by nigel on 23/02/23.
+//
+
+#include "partitionManager.h"
+
+bool partitionManager::Validate( )
+{
+
+    //auto* bootParams = getBPB(this, true);
+
+    //if(bootParams->OEM_id) {
+    //    return true;
+    //}
+
+    return true;
+
+}