Ring 3 multitasking

src/kernel/syscall.h

@@ -0,0 +1,20 @@
+#ifndef SYSCALL_H
+#define SYSCALL_H
+
+#include <stdint.h>
+
+// MSRs used for syscalls in x86_64
+#define MSR_EFER       0xC0000080
+#define MSR_STAR       0xC0000081
+#define MSR_LSTAR      0xC0000082
+#define MSR_COMPAT_STAR 0xC0000083
+#define MSR_FMASK      0xC0000084
+
+// Syscall Numbers
+#define SYS_WRITE 1
+#define SYS_EXIT  60
+
+void syscall_init(void);
+void syscall_handler_c(uint64_t syscall_num, uint64_t arg1, uint64_t arg2, uint64_t arg3, uint64_t arg4, uint64_t arg5);
+
+#endif // SYSCALL_H