Add constants for sizes

src/arch/emulate.rs

@@ -6,6 +6,7 @@ use core::{
 use std::collections::BTreeMap;
 
 use crate::{
+    MEGABYTE,
     Arch,
     MemoryArea,
     PageEntry,
@@ -94,7 +95,6 @@ impl Arch for EmulateArch {
     }
 }
 
-const MEGABYTE: usize = 1024 * 1024;
 const MEMORY_SIZE: usize = 64 * MEGABYTE;
 static MEMORY_AREAS: [MemoryArea; 1] = [
     MemoryArea {

src/lib.rs

@@ -12,6 +12,11 @@ pub use crate::{
 mod arch;
 mod page;
 
+pub const KILOBYTE: usize = 1024;
+pub const MEGABYTE: usize = KILOBYTE * KILOBYTE;
+pub const GIGABYTE: usize = KILOBYTE * MEGABYTE;
+pub const TERABYTE: usize = KILOBYTE * GIGABYTE;
+
 // Physical memory address
 #[derive(Clone, Copy, Debug, Eq, Ord, PartialEq, PartialOrd)]
 #[repr(transparent)]