Heap test passed on k210/qemu, heap size = 3M.

os/src/config.rs

@@ -3,6 +3,7 @@ pub const KERNEL_STACK_SIZE: usize = 4096 * 2;
 pub const MAX_APP_NUM: usize = 4;
 pub const APP_BASE_ADDRESS: usize = 0x80100000;
 pub const APP_SIZE_LIMIT: usize = 0x20000;
+pub const KERNEL_HEAP_SIZE: usize = 0x30_0000;
 
 #[cfg(feature = "board_k210")]
 pub const CPU_FREQ: usize = 10000000;

os/src/main.rs

@@ -4,6 +4,9 @@
 #![feature(llvm_asm)]
 #![feature(panic_info_message)]
 #![feature(const_in_array_repeat_expressions)]
+#![feature(alloc_error_handler)]
+
+extern crate alloc;
 
 #[macro_use]
 mod console;
@@ -15,6 +18,7 @@ mod loader;
 mod config;
 mod task;
 mod timer;
+mod mm;
 
 global_asm!(include_str!("entry.asm"));
 global_asm!(include_str!("link_app.S"));
@@ -33,6 +37,9 @@ fn clear_bss() {
 pub fn rust_main() -> ! {
     clear_bss();
     println!("[kernel] Hello, world!");
+    mm::init_heap();
+    mm::heap_test();
+    loop {}
     trap::init();
     loader::load_apps();
     trap::enable_interrupt();

os/src/mm/heap_allocator.rs

@@ -0,0 +1,45 @@
+use buddy_system_allocator::LockedHeap;
+use crate::config::KERNEL_HEAP_SIZE;
+
+#[global_allocator]
+static HEAP_ALLOCATOR: LockedHeap = LockedHeap::empty();
+
+#[alloc_error_handler]
+pub fn handle_alloc_error(layout: core::alloc::Layout) -> ! {
+    panic!("Heap allocation error, layout = {:?}", layout);
+}
+
+static mut HEAP_SPACE: [u8; KERNEL_HEAP_SIZE] = [0; KERNEL_HEAP_SIZE];
+
+pub fn init_heap() {
+    unsafe {
+        HEAP_ALLOCATOR
+            .lock()
+            .init(HEAP_SPACE.as_ptr() as usize, KERNEL_HEAP_SIZE);
+    }
+}
+
+#[allow(unused)]
+pub fn heap_test() {
+    use alloc::boxed::Box;
+    use alloc::vec::Vec;
+    extern "C" {
+        fn sbss();
+        fn ebss();
+    }
+    let bss_range = sbss as usize..ebss as usize;
+    let a = Box::new(5);
+    assert_eq!(*a, 5);
+    assert!(bss_range.contains(&(a.as_ref() as *const _ as usize)));
+    drop(a);
+    let mut v: Vec<usize> = Vec::new();
+    for i in 0..500 {
+        v.push(i);
+    }
+    for i in 0..500 {
+        assert_eq!(v[i], i);
+    }
+    assert!(bss_range.contains(&(v.as_ptr() as usize)));
+    drop(v);
+    println!("heap_test passed!");
+}

os/src/mm/mod.rs

@@ -0,0 +1,4 @@
+mod heap_allocator;
+
+pub use heap_allocator::init_heap;
+pub use heap_allocator::heap_test;