Struct FreeListFrameAllocator 

pub struct FreeListFrameAllocator { /* private fields */ }

A free list allocator for physical memory frames.

Maintains a list of free frames and supports allocation and deallocation. Suitable for dynamic memory management after boot.

Implementations

impl FreeListFrameAllocator

pub unsafe fn new(start: usize, end: usize) -> Self

Creates a new free list frame allocator for the given region.

Safety

The given range must be frame-aligned and not overlap with used memory.

pub unsafe fn new_static( start: usize, end: usize, backing: &mut [PhysFrame<Size4KiB>], ) -> (Self, usize)

Creates a new free list frame allocator using a static mutable slice as storage.

This avoids dynamic allocation and does not require a global allocator. The slice will be used as a stack of frames; its length determines the maximum number of frames.

Returns a tuple of the allocator and the number of frames initialized.

Safety

The caller must ensure that:

• The given range (start to end) is frame-aligned and does not overlap with any used memory.
• The backing slice is large enough to hold all frames in the region, otherwise only as many frames as fit will be initialized.
• The backing slice is not aliased elsewhere while the allocator is in use.

pub unsafe fn reset(&mut self, start: usize, end: usize)

Resets the allocator to a new region, clearing and repopulating the free list.

Safety

The given range must be frame-aligned and not overlap with used memory.

pub fn alloc_frame(&mut self) -> Option<PhysFrame<Size4KiB>>

Allocates a frame. Returns None if out of memory.

pub fn free_frame(&mut self, frame: PhysFrame<Size4KiB>)

Frees a frame, making it available for reuse.

Trait Implementations

impl FrameAllocator<Size4KiB> for FreeListFrameAllocator

fn allocate_frame(&mut self) -> Option<PhysFrame<Size4KiB>>

Allocate a frame of the appropriate size and return it if possible.