From eccb99d67d85dafea41347133bb79458b6a73a79 Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jackpot51@gmail.com>
Date: Mon, 15 Aug 2016 15:27:32 -0600
Subject: [PATCH] Use linked list allocator

---
 alloc/hole_list_allocator/Cargo.toml | 12 ++++++
 alloc/hole_list_allocator/src/lib.rs | 59 ++++++++++++++++++++++++++++
 arch/x86_64/Cargo.toml               |  2 +-
 arch/x86_64/src/lib.rs               |  3 +-
 arch/x86_64/src/main.rs              |  2 +-
 arch/x86_64/src/memory/mod.rs        |  8 ++--
 6 files changed, 79 insertions(+), 7 deletions(-)
 create mode 100644 alloc/hole_list_allocator/Cargo.toml
 create mode 100644 alloc/hole_list_allocator/src/lib.rs

diff --git a/alloc/hole_list_allocator/Cargo.toml b/alloc/hole_list_allocator/Cargo.toml
new file mode 100644
index 0000000..eba97fb
--- /dev/null
+++ b/alloc/hole_list_allocator/Cargo.toml
@@ -0,0 +1,12 @@
+[package]
+authors = ["Philipp Oppermann <dev@phil-opp.com>"]
+name = "hole_list_allocator"
+version = "0.1.0"
+
+[dependencies]
+linked_list_allocator = "0.2.0"
+spin = "0.3.5"
+
+[dependencies.lazy_static]
+version = "0.2.1"
+features = ["spin_no_std"]
diff --git a/alloc/hole_list_allocator/src/lib.rs b/alloc/hole_list_allocator/src/lib.rs
new file mode 100644
index 0000000..ddbd070
--- /dev/null
+++ b/alloc/hole_list_allocator/src/lib.rs
@@ -0,0 +1,59 @@
+#![feature(allocator)]
+#![feature(const_fn)]
+
+#![allocator]
+#![no_std]
+
+use spin::Mutex;
+use linked_list_allocator::Heap;
+
+extern crate spin;
+extern crate linked_list_allocator;
+#[macro_use]
+extern crate lazy_static;
+
+pub const HEAP_START: usize = 0x1_0000_0000; // Put at end of 4GB
+pub const HEAP_SIZE: usize = 16 * 1024 * 1024; // 16 MB
+
+lazy_static! {
+    static ref HEAP: Mutex<Heap> = Mutex::new(unsafe {
+        Heap::new(HEAP_START, HEAP_SIZE)
+    });
+}
+
+#[no_mangle]
+pub extern fn __rust_allocate(size: usize, align: usize) -> *mut u8 {
+    HEAP.lock().allocate_first_fit(size, align).expect("out of memory")
+}
+
+#[no_mangle]
+pub extern fn __rust_deallocate(ptr: *mut u8, size: usize, align: usize) {
+    unsafe { HEAP.lock().deallocate(ptr, size, align) };
+}
+
+#[no_mangle]
+pub extern fn __rust_usable_size(size: usize, _align: usize) -> usize {
+    size
+}
+
+#[no_mangle]
+pub extern fn __rust_reallocate_inplace(_ptr: *mut u8, size: usize,
+    _new_size: usize, _align: usize) -> usize
+{
+    size
+}
+
+#[no_mangle]
+pub extern fn __rust_reallocate(ptr: *mut u8, size: usize, new_size: usize,
+                                align: usize) -> *mut u8 {
+    use core::{ptr, cmp};
+
+    // from: https://github.com/rust-lang/rust/blob/
+    //     c66d2380a810c9a2b3dbb4f93a830b101ee49cc2/
+    //     src/liballoc_system/lib.rs#L98-L101
+
+    let new_ptr = __rust_allocate(new_size, align);
+    unsafe { ptr::copy(ptr, new_ptr, cmp::min(size, new_size)) };
+    __rust_deallocate(ptr, size, align);
+    new_ptr
+}
diff --git a/arch/x86_64/Cargo.toml b/arch/x86_64/Cargo.toml
index 6d6fb27..250c559 100644
--- a/arch/x86_64/Cargo.toml
+++ b/arch/x86_64/Cargo.toml
@@ -4,7 +4,7 @@ version = "0.1.0"
 
 [dependencies]
 bitflags = "*"
-bump_allocator = { path = "../../alloc/bump_allocator"}
+hole_list_allocator = { path = "../../alloc/hole_list_allocator"}
 
 [dependencies.x86]
 default-features = false
diff --git a/arch/x86_64/src/lib.rs b/arch/x86_64/src/lib.rs
index faf6e9d..79128db 100644
--- a/arch/x86_64/src/lib.rs
+++ b/arch/x86_64/src/lib.rs
@@ -9,9 +9,10 @@
 #![feature(unique)]
 #![no_std]
 
+extern crate hole_list_allocator as allocator;
+
 #[macro_use]
 extern crate bitflags;
-extern crate bump_allocator;
 extern crate x86;
 
 /// Print to console
diff --git a/arch/x86_64/src/main.rs b/arch/x86_64/src/main.rs
index 60e86ce..99147b9 100644
--- a/arch/x86_64/src/main.rs
+++ b/arch/x86_64/src/main.rs
@@ -3,7 +3,7 @@
 /// It must create the IDT with the correct entries, those entries are
 /// defined in other files inside of the `arch` module
 
-use bump_allocator::{HEAP_START, HEAP_SIZE};
+use allocator::{HEAP_START, HEAP_SIZE};
 use externs::memset;
 use gdt;
 use idt;
diff --git a/arch/x86_64/src/memory/mod.rs b/arch/x86_64/src/memory/mod.rs
index 7435413..ee79995 100644
--- a/arch/x86_64/src/memory/mod.rs
+++ b/arch/x86_64/src/memory/mod.rs
@@ -12,16 +12,16 @@ pub mod area_frame_alloc;
 static mut MEMORY_MAP: [MemoryArea; 512] = [MemoryArea { base_addr: 0, length: 0, _type: 0, acpi: 0 }; 512];
 
 /// Memory does not exist
-const MEMORY_AREA_NULL: u32 = 0;
+pub const MEMORY_AREA_NULL: u32 = 0;
 
 /// Memory is free to use
-const MEMORY_AREA_FREE: u32 = 1;
+pub const MEMORY_AREA_FREE: u32 = 1;
 
 /// Memory is reserved
-const MEMORY_AREA_RESERVED: u32 = 2;
+pub const MEMORY_AREA_RESERVED: u32 = 2;
 
 /// Memory is used by ACPI, and can be reclaimed
-const MEMORY_AREA_ACPI: u32 = 3;
+pub const MEMORY_AREA_ACPI: u32 = 3;
 
 #[derive(Clone)]
 pub struct MemoryAreaIter {