Add linked list allocator with automatic resizing

Fix memory leaks in exec
Remove warnings

src/memory/mod.rs

@@ -10,7 +10,6 @@ use spin::Mutex;
 
 pub mod bump;
 pub mod recycle;
-pub mod slab;
 
 /// The current memory map. It's size is maxed out to 512 entries, due to it being
 /// from 0x500 to 0x5000 (800 is the absolute total)

src/memory/slab.rs

@@ -1,41 +0,0 @@
-use alloc::heap::{Alloc, AllocErr, Layout};
-use spin::Mutex;
-use slab_allocator::Heap;
-
-static HEAP: Mutex<Option<Heap>> = Mutex::new(None);
-
-pub unsafe fn init_heap(offset: usize, size: usize) {
-    *HEAP.lock() = Some(Heap::new(offset, size));
-}
-
-pub struct Allocator;
-
-unsafe impl<'a> Alloc for &'a Allocator {
-    unsafe fn alloc(&mut self, layout: Layout) -> Result<*mut u8, AllocErr> {
-        if let Some(ref mut heap) = *HEAP.lock() {
-            heap.allocate(layout)
-        } else {
-            panic!("__rust_allocate: heap not initialized");
-        }
-    }
-
-    unsafe fn dealloc(&mut self, ptr: *mut u8, layout: Layout) {
-        if let Some(ref mut heap) = *HEAP.lock() {
-            heap.deallocate(ptr, layout)
-        } else {
-            panic!("__rust_deallocate: heap not initialized");
-        }
-    }
-
-    fn oom(&mut self, error: AllocErr) -> ! {
-        panic!("Out of memory: {:?}", error);
-    }
-
-    fn usable_size(&self, layout: &Layout) -> (usize, usize) {
-        if let Some(ref mut heap) = *HEAP.lock() {
-            heap.usable_size(layout)
-        } else {
-            panic!("__rust_usable_size: heap not initialized");
-        }
-    }
-}