Implemented low level disk functionality in C

Makefile

@@ -1,4 +1,4 @@
-FILES = ./build/kernel.asm.o ./build/kernel.o ./build/idt/idt.asm.o ./build/idt/idt.o ./build/memory/memory.o ./build/io/io.asm.o ./build/memory/heap/heap.o ./build/memory/heap/kheap.o ./build/memory/paging/paging.o ./build/memory/paging/paging.asm.o
+FILES = ./build/kernel.asm.o ./build/kernel.o ./build/disk/disk.o ./build/idt/idt.asm.o ./build/idt/idt.o ./build/memory/memory.o ./build/io/io.asm.o ./build/memory/heap/heap.o ./build/memory/heap/kheap.o ./build/memory/paging/paging.o ./build/memory/paging/paging.asm.o
 INCLUDES = -I./src
 FLAGS = -g -ffreestanding -falign-jumps -falign-functions -falign-labels -falign-loops -fstrength-reduce -fomit-frame-pointer -finline-functions -Wno-unused-function -fno-builtin -Werror -Wno-unused-label -Wno-cpp -Wno-unused-parameter -nostdlib -nostartfiles -nodefaultlibs -Wall -O0 -Iinc
 
@@ -45,6 +45,8 @@ all: ./bin/boot.bin ./bin/kernel.bin
 ./build/memory/paging/paging.asm.o: ./src/memory/paging/paging.asm
 	nasm -f elf -g ./src/memory/paging/paging.asm -o ./build/memory/paging/paging.asm.o
 
+./build/disk/disk.o: ./src/disk/disk.c
+	i686-elf-gcc $(INCLUDES) -I./src/disk $(FLAGS) -std=gnu99 -c ./src/disk/disk.c -o ./build/disk/disk.o
 
 clean:
 	rm -rf ./bin/boot.bin

src/disk/disk.c

@@ -0,0 +1,30 @@
+#include "io/io.h"
+int disk_read_sector(int lba, int total, void* buf)
+{
+    outb(0x1F6, (lba >> 24) | 0xE0);
+    outb(0x1F2, total);
+    outb(0x1F3, (unsigned char)(lba & 0xff));
+    outb(0x1F4, (unsigned char)(lba >> 8));
+    outb(0x1F5, (unsigned char)(lba >> 16));
+    outb(0x1F7, 0x20);
+
+    unsigned short* ptr = (unsigned short*) buf;
+    for (int b = 0; b < total; b++)
+    {
+        // Wait for the buffer to be ready
+        char c = insb(0x1F7);
+        while(!(c & 0x08))
+        {
+            c = insb(0x1F7);
+        }
+
+        // Copy from hard disk to memory
+        for (int i = 0; i < 256; i++)
+        {
+            *ptr = insw(0x1F0);
+            ptr++;
+        }
+
+    }
+    return 0;
+}

src/disk/disk.h

@@ -0,0 +1,6 @@
+#ifndef DISK_H
+#define DISK_H
+
+int disk_read_sector(int lba, int total, void* buf);
+
+#endif

src/io/io.asm

@@ -1,7 +1,7 @@
 section .asm
 
 global insb
-global insws
+global insw
 global outb
 global outw
 

src/kernel.c

@@ -4,6 +4,7 @@
 #include "idt/idt.h"
 #include "memory/heap/kheap.h"
 #include "memory/paging/paging.h"
+#include "disk/disk.h"
 
 uint16_t* video_mem = 0;
 uint16_t terminal_row = 0;
@@ -90,19 +91,12 @@ void kernel_main()
     // Switch to kernel paging chunk
     paging_switch(paging_4gb_chunk_get_directory(kernel_chunk));
 
-    char* ptr = kzalloc(4096); 
-    paging_set(paging_4gb_chunk_get_directory(kernel_chunk), (void*)0x1000, (uint32_t)ptr | PAGING_ACCESS_FROM_ALL | PAGING_IS_PRESENT | PAGING_IS_WRITEABLE);
-
     // Enable paging
     enable_paging();
 
-    char* ptr2 = (char*) 0x1000;
-    ptr2[0] = 'A';
-    ptr2[1] = 'B';
-    print(ptr2);
-
-    print(ptr);
 
+    char buf[512];
+    disk_read_sector(0, 1, buf);
 
     // Enable the system interrupts
     enable_interrupts();