allocator: import QuickFit allocator from Hypatia

This imports the QuickFit allocator from Hypatia, setting
us up to have a rudimentary kernel heap.

Signed-off-by: Dan Cross <cross@gajendra.net>

Author: Dan Cross

aarch64/src/main.rs

@@ -3,7 +3,6 @@
 #![cfg_attr(not(any(test)), no_std)]
 #![cfg_attr(not(test), no_main)]
 #![feature(alloc_error_handler)]
-#![feature(asm_const)]
 #![feature(core_intrinsics)]
 #![feature(strict_provenance)]
 #![forbid(unsafe_op_in_unsafe_fn)]

aarch64/src/runtime.rs

@@ -5,7 +5,7 @@ extern crate alloc;
 use crate::kmem::physaddr_as_virt;
 use crate::registers::rpi_mmio;
 use crate::uartmini::MiniUart;
-use alloc::alloc::{GlobalAlloc, Layout};
+use alloc::alloc::Layout;
 use core::fmt::Write;
 use core::panic::PanicInfo;
 use port::devcons::PanicConsole;
@@ -39,17 +39,3 @@ pub fn panic(info: &PanicInfo) -> ! {
 fn oom(_layout: Layout) -> ! {
     panic!("oom");
 }
-
-struct FakeAlloc;
-
-unsafe impl GlobalAlloc for FakeAlloc {
-    unsafe fn alloc(&self, _layout: Layout) -> *mut u8 {
-        panic!("fake alloc");
-    }
-    unsafe fn dealloc(&self, _ptr: *mut u8, _layout: Layout) {
-        panic!("fake dealloc");
-    }
-}
-
-#[global_allocator]
-static FAKE_ALLOCATOR: FakeAlloc = FakeAlloc {};

lib/aarch64-unknown-none-elf.json

@@ -1,6 +1,6 @@
 {
 	"arch": "aarch64",
-	"data-layout": "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128",
+	"data-layout": "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128-Fn32",
 	"disable-redzone": true,
 	"executables": true,
 	"features": "+strict-align,+neon,+fp-armv8",
@@ -16,4 +16,4 @@
 			"-nostdlib"
 		]
 	}
-}
+}