impl Step for Page

Author: Freax13

src/structures/paging/page.rs

@@ -4,6 +4,8 @@ use crate::structures::paging::page_table::PageTableLevel;
 use crate::structures::paging::PageTableIndex;
 use crate::VirtAddr;
 use core::fmt;
+#[cfg(feature = "step_trait")]
+use core::iter::Step;
 use core::marker::PhantomData;
 use core::ops::{Add, AddAssign, Sub, SubAssign};
 
@@ -274,6 +276,32 @@ impl<S: PageSize> Sub<Self> for Page<S> {
     }
 }
 
+#[cfg(feature = "step_trait")]
+impl<S: PageSize> Step for Page<S> {
+    fn steps_between(start: &Self, end: &Self) -> Option<usize> {
+        Step::steps_between(&start.start_address, &end.start_address)
+            .map(|steps| steps / S::SIZE as usize)
+    }
+
+    fn forward_checked(start: Self, count: usize) -> Option<Self> {
+        let count = count.checked_mul(S::SIZE as usize)?;
+        let start_address = Step::forward_checked(start.start_address, count)?;
+        Some(Self {
+            start_address,
+            size: PhantomData,
+        })
+    }
+
+    fn backward_checked(start: Self, count: usize) -> Option<Self> {
+        let count = count.checked_mul(S::SIZE as usize)?;
+        let start_address = Step::backward_checked(start.start_address, count)?;
+        Some(Self {
+            start_address,
+            size: PhantomData,
+        })
+    }
+}
+
 /// A range of pages with exclusive upper bound.
 #[derive(Clone, Copy, PartialEq, Eq, Hash)]
 #[repr(C)]