You cannot select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

71 lines
2.1 KiB
Rust

// SPDX-License-Identifier: MIT OR Apache-2.0
//
// Copyright (c) 2021-2022 Andre Richter <andre.o.richter@gmail.com>
//! Allocation.
use super::MemoryRegion;
use crate::{
memory::{AddressType, Virtual},
synchronization::IRQSafeNullLock,
warn,
};
use core::num::NonZeroUsize;
//--------------------------------------------------------------------------------------------------
// Public Definitions
//--------------------------------------------------------------------------------------------------
/// A page allocator that can be lazyily initialized.
pub struct PageAllocator<ATYPE: AddressType> {
pool: Option<MemoryRegion<ATYPE>>,
}
//--------------------------------------------------------------------------------------------------
// Global instances
//--------------------------------------------------------------------------------------------------
static KERNEL_MMIO_VA_ALLOCATOR: IRQSafeNullLock<PageAllocator<Virtual>> =
IRQSafeNullLock::new(PageAllocator::new());
//--------------------------------------------------------------------------------------------------
// Public Code
//--------------------------------------------------------------------------------------------------
/// Return a reference to the kernel's MMIO virtual address allocator.
pub fn kernel_mmio_va_allocator() -> &'static IRQSafeNullLock<PageAllocator<Virtual>> {
&KERNEL_MMIO_VA_ALLOCATOR
}
impl<ATYPE: AddressType> PageAllocator<ATYPE> {
/// Create an instance.
pub const fn new() -> Self {
Self { pool: None }
}
/// Initialize the allocator.
pub fn initialize(&mut self, pool: MemoryRegion<ATYPE>) {
if self.pool.is_some() {
warn!("Already initialized");
return;
}
self.pool = Some(pool);
}
/// Allocate a number of pages.
pub fn alloc(
&mut self,
num_requested_pages: NonZeroUsize,
) -> Result<MemoryRegion<ATYPE>, &'static str> {
if self.pool.is_none() {
return Err("Allocator not initialized");
}
self.pool
.as_mut()
.unwrap()
.take_first_n_pages(num_requested_pages)
}
}