Kernel: Atomic frame allocator

Make the frame allocator atomic. This allows allocating frames from
multiple CPU cores without having to go through a global lock.

kernel/src/arch/i386/gdt.rs

@@ -19,7 +19,7 @@ use crate::arch::i386::instructions::segmentation::*;
 
 use crate::paging::PAGE_SIZE;
 use crate::paging::{MappingAccessRights, kernel_memory::get_kernel_memory};
-use crate::frame_allocator::{FrameAllocator, FrameAllocatorTrait};
+use crate::frame_allocator::FrameAllocator;
 use crate::mem::VirtualAddress;
 use alloc::vec::Vec;
 use crate::utils::align_up;

kernel/src/arch/i386/stack.rs

@@ -29,7 +29,7 @@
 use ::core::mem::size_of;
 use crate::paging::lands::{VirtualSpaceLand, UserLand, KernelLand};
 use crate::paging::{PAGE_SIZE, process_memory::QueryMemory, MappingAccessRights, PageState, kernel_memory::get_kernel_memory};
-use crate::frame_allocator::{FrameAllocator, FrameAllocatorTrait};
+use crate::frame_allocator::FrameAllocator;
 use crate::mem::VirtualAddress;
 use crate::error::KernelError;
 use xmas_elf::ElfFile;

kernel/src/frame_allocator/physical_mem_region.rs

@@ -2,7 +2,7 @@
 //!
 //! A [PhysicalMemRegion] is a span of consecutive physical frames.
 
-use super::{FrameAllocator, FrameAllocatorTraitPrivate};
+use super::FrameAllocator;
 use crate::paging::PAGE_SIZE;
 use crate::mem::PhysicalAddress;
 use crate::utils::{align_down, div_ceil, check_aligned, Splittable};
@@ -209,11 +209,12 @@ impl Splittable for Vec<PhysicalMemRegion> {
 
 #[cfg(test)]
 mod test {
- use super::super::{FrameAllocator, FrameAllocatorTrait};
+ use super::super::{FrameAllocator, FRAME_ALLOCATOR};
  use super::{PhysicalMemRegion, PhysicalMemRegionIter};
  use crate::utils::Splittable;
  use crate::mem::PhysicalAddress;
  use crate::paging::PAGE_SIZE;
+ use core::sync::atomic::Ordering;
 
  #[test]
  #[should_panic]
@@ -226,8 +227,7 @@ mod test {
  fn on_fixed_mmio_rounds_unaligned() {
  let _f = crate::frame_allocator::init();
  // reserve them so we don't panic
- crate::frame_allocator::mark_frame_bootstrap_allocated(PhysicalAddress(0));
- crate::frame_allocator::mark_frame_bootstrap_allocated(PhysicalAddress(PAGE_SIZE));
+ FRAME_ALLOCATOR.mark_area_reserved(0, 0x1FFF);
 
  let region = unsafe { PhysicalMemRegion::on_fixed_mmio(PhysicalAddress(0x00000007), PAGE_SIZE + 1) };
  assert_eq!(region.start_addr, 0);

kernel/src/heap_allocator.rs

@@ -8,7 +8,7 @@ use core::ops::Deref;
 use core::ptr::NonNull;
 use linked_list_allocator::{Heap, align_up};
 use crate::paging::{PAGE_SIZE, MappingAccessRights, kernel_memory::get_kernel_memory};
-use crate::frame_allocator::{FrameAllocator, FrameAllocatorTrait};
+use crate::frame_allocator::FrameAllocator;
 use crate::mem::VirtualAddress;
 
 /// Simple wrapper around linked_list_allocator, growing heap by allocating pages

kernel/src/main.rs

@@ -6,7 +6,7 @@
 //! Currently doesn't do much, besides booting and printing Hello World on the
 //! screen. But hey, that's a start.
 
-#![feature(lang_items, start, asm, global_asm, compiler_builtins_lib, naked_functions, core_intrinsics, const_fn, abi_x86_interrupt, allocator_api, alloc, box_syntax, no_more_cas, const_vec_new, range_contains, step_trait, thread_local, nll)]
+#![feature(lang_items, start, asm, global_asm, compiler_builtins_lib, naked_functions, core_intrinsics, const_fn, abi_x86_interrupt, allocator_api, alloc, box_syntax, no_more_cas, const_vec_new, range_contains, step_trait, thread_local, nll, untagged_unions, maybe_uninit, const_fn_union)]
 #![no_std]
 #![cfg_attr(target_os = "none", no_main)]
 #![recursion_limit = "1024"]

kernel/src/mem.rs

@@ -176,6 +176,12 @@ impl VirtualAddress {
 
  /// Rounds up PAGE_SIZE.
  pub fn ceil(self) -> VirtualAddress { VirtualAddress(round_to_page_upper(self.0)) }
+
+ /// Wrapping (modular) addition. Computes self + rhs, wrapping around at the boundary of the type.
+ pub fn wrapping_add(self, rhs: usize) -> VirtualAddress { VirtualAddress(self.0.wrapping_add(rhs)) }
+
+ /// Wrapping (modular) substraction. Computes self - rhs, wrapping around at the boundary of the type.
+ pub fn wrapping_sub(self, rhs: usize) -> VirtualAddress { VirtualAddress(self.0.wrapping_sub(rhs)) }
 }
 
 impl core::iter::Step for PhysicalAddress {

kernel/src/paging/arch/i386/table.rs

@@ -10,7 +10,7 @@ use super::super::super::lands::{KernelLand, UserLand, VirtualSpaceLand};
 use super::super::super::kernel_memory::get_kernel_memory;
 use super::super::super::MappingAccessRights;
 use crate::mem::{VirtualAddress, PhysicalAddress};
-use crate::frame_allocator::{PhysicalMemRegion, FrameAllocator, FrameAllocatorTrait};
+use crate::frame_allocator::{PhysicalMemRegion, FrameAllocator};
 use core::fmt::{Debug, Formatter, Error};
 
 /// When paging is on, accessing this address loops back to the directory itself thanks to

kernel/src/paging/mapping.rs

@@ -218,7 +218,7 @@ mod test {
  use super::MappingType;
  use crate::mem::{VirtualAddress, PhysicalAddress};
  use crate::paging::PAGE_SIZE;
- use crate::frame_allocator::{PhysicalMemRegion, FrameAllocator, FrameAllocatorTrait};
+ use crate::frame_allocator::{PhysicalMemRegion, FrameAllocator};
  use std::sync::Arc;
  use std::vec::Vec;
  use crate::utils::Splittable;

kernel/src/paging/process_memory.rs

@@ -26,7 +26,7 @@ use super::cross_process::CrossProcessMapping;
 use super::error::MmError;
 use super::MappingAccessRights;
 use crate::mem::{VirtualAddress, PhysicalAddress};
-use crate::frame_allocator::{FrameAllocator, FrameAllocatorTrait, PhysicalMemRegion};
+use crate::frame_allocator::{FrameAllocator, PhysicalMemRegion};
 use crate::paging::arch::Entry;
 use crate::error::KernelError;
 use crate::utils::{check_aligned, check_nonzero_length};

kernel/src/syscalls.rs

@@ -3,7 +3,7 @@
 use crate::mem::{VirtualAddress, PhysicalAddress};
 use crate::mem::{UserSpacePtr, UserSpacePtrMut};
 use crate::paging::{MappingAccessRights, mapping::MappingType};
-use crate::frame_allocator::{PhysicalMemRegion, FrameAllocator, FrameAllocatorTrait};
+use crate::frame_allocator::{PhysicalMemRegion, FrameAllocator};
 use crate::process::{Handle, ThreadStruct, ProcessStruct};
 use crate::event::{self, Waitable};
 use crate::scheduler::{self, get_current_thread, get_current_process};