kernel/mem/
allocator.rs

1use core::alloc::GlobalAlloc;
2use core::sync::atomic::{AtomicUsize, Ordering};
3
4use slab_allocator_rs::LockedHeap;
5
6use crate::early_println;
7use crate::vm::vmem::MemoryArea;
8
9#[global_allocator]
10// Keep the allocator state out of .bss to avoid relying on late-bss pages being
11// accessible on all accelerators (e.g. HVF). The value is still initialized to
12// the same zero state.
13#[unsafe(link_section = ".data")]
14static ALLOCATOR: Allocator = Allocator::new();
15
16struct Allocator {
17    // inner: Option<Talck<spin::Mutex<()>, ClaimOnOom>>,
18    inner: spin::Once<LockedHeap>,
19    allocated_count: AtomicUsize,
20    allocated_bytes: AtomicUsize,
21}
22
23unsafe impl GlobalAlloc for Allocator {
24    unsafe fn alloc(&self, layout: core::alloc::Layout) -> *mut u8 {
25        if let Some(inner) = self.inner.get() {
26            // early_println!("Allocating {} bytes with alignment {}", layout.size(), layout.align());
27            let ptr = unsafe { inner.alloc(layout) };
28            // early_println!("Allocated {} bytes at {:?}", layout.size(), ptr);
29            self.allocated_count.fetch_add(1, Ordering::SeqCst);
30            self.allocated_bytes
31                .fetch_add(layout.size(), Ordering::SeqCst);
32            // early_println!("Total allocations: {}, Total bytes allocated: {}", self.allocated_count.load(Ordering::SeqCst), self.allocated_bytes.load(Ordering::SeqCst));
33            return ptr;
34        }
35        panic!("Allocator not initialized, cannot allocate memory.");
36    }
37
38    unsafe fn dealloc(&self, ptr: *mut u8, layout: core::alloc::Layout) {
39        if let Some(inner) = self.inner.get() {
40            unsafe { inner.dealloc(ptr, layout) }
41            // early_println!("Deallocated {} bytes at {:?}", layout.size(), ptr);
42            self.allocated_count.fetch_sub(1, Ordering::SeqCst);
43            self.allocated_bytes
44                .fetch_sub(layout.size(), Ordering::SeqCst);
45            return;
46        }
47        panic!("Allocator not initialized, cannot deallocate memory.");
48    }
49}
50
51impl Allocator {
52    pub const fn new() -> Self {
53        Allocator {
54            inner: spin::Once::new(),
55            allocated_count: AtomicUsize::new(0),
56            allocated_bytes: AtomicUsize::new(0),
57        }
58    }
59
60    pub unsafe fn init(&self, start: usize, size: usize) {
61        let _ = self
62            .inner
63            .call_once(|| unsafe { LockedHeap::new(start, size) });
64    }
65}
66
67pub fn init_heap(area: MemoryArea) {
68    let size = area.size();
69    if size == 0 {
70        early_println!("Heap size is zero, skipping initialization.");
71        return;
72    }
73
74    unsafe {
75        ALLOCATOR.init(area.start, size);
76    }
77
78    early_println!("Heap initialized: {:#x} - {:#x}", area.start, area.end);
79}
kernel/mem/allocator.rs

kernel/mem/
allocator.rs
