Implement core::iter::Step trait for for PhysFrame

Cargo.toml

@@ -37,11 +37,12 @@ cc = { version = "1.0.37", optional = true }
 default = [ "nightly", "instructions" ]
 instructions = []
 external_asm = [ "cc" ]
-nightly = [ "inline_asm", "const_fn", "abi_x86_interrupt", "doc_cfg" ]
+nightly = [ "inline_asm", "const_fn", "abi_x86_interrupt", "doc_cfg", "step_trait" ]
 inline_asm = []
 abi_x86_interrupt = []
 const_fn = []
 doc_cfg = []
+step_trait = []
 
 [package.metadata.release]
 no-dev-version = true

src/addr.rs

@@ -529,6 +529,25 @@ impl Sub<PhysAddr> for PhysAddr {
     }
 }
 
+#[cfg(feature = "step_trait")]
+impl core::iter::Step for PhysAddr {
+    fn steps_between(start: &Self, end: &Self) -> Option<usize> {
+        if *start <= *end {
+            Some((*end - *start) as usize)
+        } else {
+            None
+        }
+    }
+
+    fn forward_checked(start: Self, count: usize) -> Option<Self> {
+        start.as_u64().checked_add(count as u64).map(PhysAddr::new)
+    }
+
+    fn backward_checked(start: Self, count: usize) -> Option<Self> {
+        start.as_u64().checked_sub(count as u64).map(PhysAddr::new)
+    }
+}
+
 /// Align address downwards.
 ///
 /// Returns the greatest `x` with alignment `align` so that `x <= addr`.

src/lib.rs

@@ -9,7 +9,7 @@
 #![cfg_attr(feature = "inline_asm", feature(asm))]
 #![cfg_attr(feature = "abi_x86_interrupt", feature(abi_x86_interrupt))]
 #![cfg_attr(feature = "doc_cfg", feature(doc_cfg))]
-#![warn(missing_docs)]
+#![cfg_attr(feature = "step_trait", feature(step_trait))]
 #![deny(missing_debug_implementations)]
 
 pub use crate::addr::{align_down, align_up, PhysAddr, VirtAddr};

src/structures/paging/frame.rs

@@ -132,6 +132,23 @@ impl<S: PageSize> Sub<PhysFrame<S>> for PhysFrame<S> {
     }
 }
 
+#[cfg(feature = "step_trait")]
+impl<S: PageSize> core::iter::Step for PhysFrame<S> {
+    fn steps_between(start: &Self, end: &Self) -> Option<usize> {
+        PhysAddr::steps_between(&start.start_address, &end.start_address)
+    }
+
+    fn forward_checked(start: Self, count: usize) -> Option<Self> {
+        PhysAddr::forward_checked(start.start_address, count)
+            .and_then(|start_addr| Self::from_start_address(start_addr).ok())
+    }
+
+    fn backward_checked(start: Self, count: usize) -> Option<Self> {
+        PhysAddr::backward_checked(start.start_address, count)
+            .and_then(|start_addr| Self::from_start_address(start_addr).ok())
+    }
+}
+
 /// An range of physical memory frames, exclusive the upper bound.
 #[derive(Clone, Copy, PartialEq, Eq)]
 #[repr(C)]