Testing

bootloader/stage2.asm

@@ -11,7 +11,9 @@ jmp second_step
 
 %include "intel_16.asm"
 
+FREE_SEGMENT equ 0x5000
 FREE_BASE equ 0x4500
+
 KERNEL_BASE equ 0x600      ; 0x600:0x0 (0x6000)
 
 DAP:
@@ -42,7 +44,7 @@ second_step:
     mov ds, ax
 
     ; Used for disk access
-    xor ax, ax
+    mov ax, FREE_SEGMENT
     mov gs, ax
 
     mov si, load_kernel
@@ -52,7 +54,7 @@ second_step:
 
     mov byte [DAP.count], 1
     mov word [DAP.offset], FREE_BASE
-    mov word [DAP.segment], 0
+    mov word [DAP.segment], FREE_SEGMENT
     mov dword [DAP.lba], 0
 
     call extended_read
@@ -64,7 +66,7 @@ second_step:
 
     mov byte [DAP.count], 1
     mov word [DAP.offset], FREE_BASE
-    mov word [DAP.segment], 0
+    mov word [DAP.segment], FREE_SEGMENT
 
     mov di, [partition_start]
     mov word [DAP.lba], di
@@ -115,7 +117,7 @@ second_step:
     mov ah, [sectors_per_cluster]
     mov byte [DAP.count], ah
     mov word [DAP.offset], FREE_BASE
-    mov word [DAP.segment], 0
+    mov word [DAP.segment], FREE_SEGMENT
 
     ; Compute LBA from root_dir_start
     mov ax, [root_dir_start]
@@ -212,6 +214,12 @@ second_step:
     mov si, star
     call print_16
 
+    mov di, [current_segment]
+    call print_int_16
+
+    mov si, star
+    call print_16
+
     movzx ax, [sectors_per_cluster]
     mov word [DAP.count], ax
     mov word [DAP.offset], 0x0
@@ -229,6 +237,15 @@ second_step:
 
     mov word [DAP.lba], ax
 
+    mov di, ax
+    call print_int_16
+
+    mov si, star
+    call print_16
+
+    mov di, [current_cluster]
+    call print_int_16
+
     call extended_read
 
     mov ax, [loaded_clusters]
@@ -247,7 +264,7 @@ second_step:
     ; Read the FAT sector
     mov word [DAP.count], 1
     mov word [DAP.offset], FREE_BASE
-    mov word [DAP.segment], 0x0
+    mov word [DAP.segment], FREE_SEGMENT
     mov word [DAP.lba], ax
 
     call extended_read

kernel/include/e820.hpp

@@ -31,8 +31,8 @@ struct bios_e820_entry {
     uint16_t acpi;
 } __attribute__((packed));
 
-extern int16_t bios_e820_entry_count;
+//extern bios_e820_entry bios_e820_entries[MAX_E820_ENTRIES];
-extern bios_e820_entry bios_e820_entries[MAX_E820_ENTRIES];
+//extern int16_t bios_e820_entry_count;
 
 struct mmapentry {
     uint64_t base;

kernel/src/boot/boot_16.cpp

@@ -31,9 +31,8 @@ typedef uint64_t size_t;
 #define CODE_16
 #include "e820.hpp" //Just for the address of the e820 map
 
-
+//e820::bios_e820_entry e820::bios_e820_entries[e820::MAX_E820_ENTRIES];
-e820::bios_e820_entry e820::bios_e820_entries[e820::MAX_E820_ENTRIES];
+//int16_t e820::bios_e820_entry_count = 0;
-int16_t e820::bios_e820_entry_count = 0;
 
 namespace {
 
@@ -66,7 +65,8 @@ void reset_segments(){
 }
 
 int detect_memory_e820(){
-    auto smap = &e820::bios_e820_entries[0];
+    auto smap = reinterpret_cast<e820::bios_e820_entry*>(0x5008);
+    //auto smap = &e820::bios_e820_entries[0];
 
     uint16_t entries = 0;
 
@@ -99,7 +99,10 @@ int detect_memory_e820(){
 void detect_memory(){
     //TODO If e820 fails, try other solutions to get memory map
 
-    e820::bios_e820_entry_count = detect_memory_e820();
+    auto t = detect_memory_e820();
+    //asm volatile("xchg bx, bx");
+    *reinterpret_cast<int16_t*>(0x5000) = t;
+    //asm volatile("xchg bx, bx");
 }
 
 void disable_interrupts(){

kernel/src/e820.cpp

@@ -15,9 +15,11 @@ size_t _available_memory;
 } //end of namespace anonymous
 
 void e820::finalize_memory_detection(){
-    if(bios_e820_entry_count > 0){
+    auto t = *reinterpret_cast<int16_t*>(0x5000);
-        for(int64_t i = 0; i < bios_e820_entry_count; ++i){
+    auto smap = reinterpret_cast<e820::bios_e820_entry*>(0x5008);
-            auto& bios_entry = bios_e820_entries[i];
+    if(t > 0){
+        for(int64_t i = 0; i < t; ++i){
+            auto& bios_entry = smap[i];
             auto& os_entry = e820_mmap[i];
 
             uint64_t base = bios_entry.base_low + (static_cast<uint64_t>(bios_entry.base_high) << 32);
@@ -39,11 +41,14 @@ void e820::finalize_memory_detection(){
 }
 
 uint64_t e820::mmap_entry_count(){
-    return bios_e820_entry_count;
+    auto t = *reinterpret_cast<int16_t*>(0x5000);
+    return t;
+    //return bios_e820_entry_count;
 }
 
 bool e820::mmap_failed(){
-    return bios_e820_entry_count <= 0;
+    auto t = *reinterpret_cast<int16_t*>(0x5000);
+    return t <= 0;
 }
 
 const e820::mmapentry& e820::mmap_entry(uint64_t i){

kernel/src/memory.cpp

@@ -120,10 +120,16 @@ uint64_t* allocate_block(uint64_t blocks){
         }
     }
 
+    asm volatile("xchg bx, bx");
+
+
     if(!current_mmap_entry){
         return nullptr;
     }
 
+
+
+
     auto block = reinterpret_cast<uint64_t*>(current_mmap_entry_position);
 
     paging::identity_map(block, blocks);
@@ -206,16 +212,22 @@ void init_head(){
 }
 
 void expand_heap(malloc_header_chunk* current){
+    asm volatile("xchg bx, bx");
+
     //Allocate a new block of memory
     uint64_t* block = allocate_block(MIN_BLOCKS);
 
     //Transform it into a malloc chunk
     auto header = reinterpret_cast<malloc_header_chunk*>(block);
 
+    asm volatile("xchg bx, bx");
+
     //Update the sizes
     header->size() = MIN_BLOCKS * BLOCK_SIZE - META_SIZE;
     header->footer()->size() = header->size();
 
+    asm volatile("xchg bx, bx");
+
     //Insert the new block into the free list
     insert_after(current, header);
 }

kernel/src/shell.cpp

@@ -103,7 +103,7 @@ command_definition commands[26] = {
 
 std::string current_input(16);
 
-void exec_command();
+void exec_shell_command();
 
 template<bool Enable = History>
 void history_key(char key){
@@ -166,7 +166,7 @@ void start_shell(){
                 k_print_line();
 
                 if(current_input.size() > 0){
-                    exec_command();
+                    exec_shell_command();
 
                     if(get_column() != 0){
                         k_print_line();
@@ -202,7 +202,7 @@ void start_shell(){
     }
 }
 
-void exec_command(){
+void exec_shell_command(){
     history_save();
 
     auto params = std::split(current_input);;