Files
redox-kernel/src/allocator/linked_list.rs
2019-10-06 11:04:06 -06:00

56 lines
1.8 KiB
Rust

use core::alloc::{AllocErr, GlobalAlloc, Layout};
use core::ptr::{self, NonNull};
use linked_list_allocator::Heap;
use spin::Mutex;
use crate::paging::ActivePageTable;
static HEAP: Mutex<Option<Heap>> = Mutex::new(None);
pub struct Allocator;
impl Allocator {
pub unsafe fn init(offset: usize, size: usize) {
*HEAP.lock() = Some(Heap::new(offset, size));
}
}
unsafe impl GlobalAlloc for Allocator {
unsafe fn alloc(&self, layout: Layout) -> *mut u8 {
loop {
let res = if let Some(ref mut heap) = *HEAP.lock() {
heap.allocate_first_fit(layout)
} else {
panic!("__rust_allocate: heap not initialized");
};
match res {
Err(AllocErr) => {
let size = if let Some(ref heap) = *HEAP.lock() {
heap.size()
} else {
panic!("__rust_allocate: heap not initialized");
};
super::map_heap(&mut ActivePageTable::new(), crate::KERNEL_HEAP_OFFSET + size, crate::KERNEL_HEAP_SIZE);
if let Some(ref mut heap) = *HEAP.lock() {
heap.extend(crate::KERNEL_HEAP_SIZE);
} else {
panic!("__rust_allocate: heap not initialized");
}
},
other => return other.ok().map_or(ptr::null_mut(), |allocation| allocation.as_ptr()),
}
}
}
unsafe fn dealloc(&self, ptr: *mut u8, layout: Layout) {
if let Some(ref mut heap) = *HEAP.lock() {
heap.deallocate(NonNull::new_unchecked(ptr), layout)
} else {
panic!("__rust_deallocate: heap not initialized");
}
}
}