syscalls

1 files changed, 19 insertions, 5 deletions

diff --git a/kernel/gdt.c b/kernel/gdt.c
index 4df089f..562fbd5 100644
--- a/kernel/gdt.c
+++ b/kernel/gdt.c
@@ -1,14 +1,28 @@
-#include "kernel/kernel.h"
 // http://wiki.osdev.org/GDT_Tutorial
+#include "kernel/kernel.h"
+#include "kernel/gdt.h"
 
 #include "usermode.h"
 
 #include <stdint.h>
+
 #define GDT_SIZE 6
+static uint8_t gdt_struct[GDT_SIZE*8]; // GLOBAL DESCRIPTOR TABLE
+uint64_t gdt_descriptor;
 
-extern sys_tss;
-static uint8_t gdt_struct[GDT_SIZE*8];
+//https://wiki.osdev.org/Task_State_Segment
+tss_struct sys_tss; //Define the TSS as a global structure
 
+void install_tss(uint32_t esp0){
+
+    // now fill each value
+    // set values necessary
+    sys_tss.ss0 = 0x10;            //kernel data
+    sys_tss.esp0 = esp0;
+
+    // now set the IO bitmap (not necessary, so set above limit)       
+    // sys_tss.iomap = ( unsigned short ) sizeof( tss_struct ); 
+}
 typedef struct GDT_struct
 {
     uint32_t base;
@@ -130,7 +144,7 @@ void gdt_init()
         encodeGdtEntry(&gdt_struct[8*i],myGDT[i]);
 
     // update tss entry
-    install_tss();
+    install_tss(0);
 
-    setup_gdt(&gdt_struct[0],8*GDT_SIZE);
+    asm_setup_gdt(&gdt_struct[0],8*GDT_SIZE);
 }