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x86-64/mm: better VMA allocator

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This commit is contained in:
Mark Poliakov 2023-10-01 16:58:46 +03:00
parent 03180a1561
commit 6cedfa7c4a
30 changed files with 933 additions and 530 deletions
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1
Cargo.toml
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@ -15,6 +15,7 @@ memfs = { path = "lib/memfs" }
device-api = { path = "lib/device-api", features = ["derive"] }
kernel-util = { path = "lib/kernel-util" }
memtables = { path = "lib/memtables" }
vmalloc = { path = "lib/vmalloc" }
atomic_enum = "0.2.0"
bitflags = "2.3.3"

13
lib/vmalloc/Cargo.toml Normal file
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@ -0,0 +1,13 @@
[package]
name = "vmalloc"
version = "0.1.0"
edition = "2021"
# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
[dependencies]
yggdrasil-abi = { git = "https://git.alnyan.me/yggdrasil/yggdrasil-abi.git" }
[dev-dependencies]
itertools = "0.11.0"
proptest = "1.2.0"

349
lib/vmalloc/src/allocator.rs Normal file
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@ -0,0 +1,349 @@
use core::cmp::Ordering;
use alloc::collections::{linked_list::CursorMut, LinkedList};
use yggdrasil_abi::error::Error;
use crate::VirtualMemoryRange;
#[derive(PartialEq, Clone, Debug, Copy)]
struct AllocatorNode {
range: VirtualMemoryRange,
used: bool,
}
impl PartialOrd for AllocatorNode {
fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
self.range.start_pfn.partial_cmp(&other.range.start_pfn)
}
}
pub struct TreeAllocator {
ranges: LinkedList<AllocatorNode>,
}
impl AllocatorNode {
pub const fn free(start_pfn: usize, end_pfn: usize) -> Self {
Self {
range: VirtualMemoryRange { start_pfn, end_pfn },
used: false,
}
}
#[cfg(test)]
pub const fn used(start_pfn: usize, end_pfn: usize) -> Self {
Self {
range: VirtualMemoryRange { start_pfn, end_pfn },
used: true,
}
}
#[inline]
pub const fn pfn_count(&self) -> usize {
self.range.end_pfn - self.range.start_pfn
}
}
impl TreeAllocator {
pub fn new(start_pfn: usize, end_pfn: usize) -> Self {
let mut ranges = LinkedList::new();
ranges.push_back(AllocatorNode::free(start_pfn, end_pfn));
Self { ranges }
}
fn find_region_mut<F: Fn(&AllocatorNode) -> bool>(&mut self, f: F) -> CursorMut<AllocatorNode> {
let mut cursor = self.ranges.cursor_front_mut();
while let Some(range) = cursor.current() {
if f(range) {
break;
}
cursor.move_next();
}
cursor
}
fn coalesce_regions(&mut self) {
let mut cursor = self.ranges.cursor_front_mut();
loop {
let Some(&mut next) = cursor.peek_next() else {
break;
};
let current = cursor.current().unwrap();
if current.used == next.used {
debug_assert_eq!(current.range.end_pfn, next.range.start_pfn);
current.range.end_pfn = next.range.end_pfn;
cursor.move_next();
cursor.remove_current();
cursor.move_prev();
} else {
cursor.move_next();
}
}
}
fn set_range(
&mut self,
start_pfn: usize,
pfn_count: usize,
old_state: bool,
new_state: bool,
) -> Result<(), Error> {
let insert = VirtualMemoryRange {
start_pfn,
end_pfn: start_pfn + pfn_count,
};
let mut cursor = self.find_region_mut(|r| r.used == old_state && r.range.contains(&insert));
let range = cursor.current().ok_or(Error::AlreadyExists)?;
let start_pfn = range.range.start_pfn;
let end_pfn = range.range.end_pfn;
match (insert.start_pfn == start_pfn, insert.end_pfn == end_pfn) {
// No split
(true, true) => {
range.used = new_state;
}
// Split start
(true, false) => {
range.used = new_state;
range.range.end_pfn = insert.end_pfn;
cursor.insert_after(AllocatorNode {
range: VirtualMemoryRange {
start_pfn: insert.end_pfn,
end_pfn,
},
used: old_state,
});
}
// Split end
(false, true) => {
range.range.end_pfn = insert.start_pfn;
cursor.insert_after(AllocatorNode {
range: VirtualMemoryRange {
start_pfn: insert.start_pfn,
end_pfn,
},
used: new_state,
});
}
// Split in the middle
(false, false) => {
range.range = insert;
range.used = new_state;
cursor.insert_after(AllocatorNode {
range: VirtualMemoryRange {
start_pfn: insert.end_pfn,
end_pfn,
},
used: old_state,
});
cursor.insert_before(AllocatorNode {
range: VirtualMemoryRange {
start_pfn,
end_pfn: insert.start_pfn,
},
used: old_state,
});
}
}
self.coalesce_regions();
Ok(())
}
pub fn insert(&mut self, start_pfn: usize, pfn_count: usize) -> Result<(), Error> {
self.set_range(start_pfn, pfn_count, false, true)
}
pub fn free(&mut self, start_pfn: usize, pfn_count: usize) -> Result<(), Error> {
self.set_range(start_pfn, pfn_count, true, false)
}
pub fn allocate(&mut self, pfn_count: usize) -> Option<usize> {
let mut cursor = self.find_region_mut(|r| !r.used && r.pfn_count() >= pfn_count);
let range = cursor.current()?;
let start_pfn = range.range.start_pfn;
let end_pfn = range.range.end_pfn;
range.used = true;
if range.pfn_count() > pfn_count {
range.range.end_pfn = start_pfn + pfn_count;
// Split the range
cursor.insert_after(AllocatorNode::free(start_pfn + pfn_count, end_pfn));
}
self.coalesce_regions();
Some(start_pfn)
}
pub fn ranges(&self) -> impl Iterator<Item = (bool, VirtualMemoryRange)> + '_ {
self.ranges.iter().map(|r| (r.used, r.range))
}
}
#[cfg(test)]
mod tests {
use alloc::collections::LinkedList;
use super::{AllocatorNode, TreeAllocator};
extern crate std;
#[test]
fn deallocation() {
let ranges = LinkedList::from_iter([
AllocatorNode::free(0, 12),
AllocatorNode::used(12, 24),
AllocatorNode::free(24, 32),
AllocatorNode::used(32, 64),
AllocatorNode::free(64, 128),
]);
let mut alloc = TreeAllocator { ranges };
// No-split dealloc
assert_eq!(alloc.free(12, 12), Ok(()));
let expected = LinkedList::from_iter([
AllocatorNode::free(0, 32),
AllocatorNode::used(32, 64),
AllocatorNode::free(64, 128),
]);
itertools::assert_equal(alloc.ranges.iter(), expected.iter());
// Split at the start dealloc
assert_eq!(alloc.free(32, 8), Ok(()));
let expected = LinkedList::from_iter([
AllocatorNode::free(0, 40),
AllocatorNode::used(40, 64),
AllocatorNode::free(64, 128),
]);
itertools::assert_equal(alloc.ranges.iter(), expected.iter());
// Split at the end dealloc
assert_eq!(alloc.free(56, 8), Ok(()));
let expected = LinkedList::from_iter([
AllocatorNode::free(0, 40),
AllocatorNode::used(40, 56),
AllocatorNode::free(56, 128),
]);
itertools::assert_equal(alloc.ranges.iter(), expected.iter());
// Split in the middle
assert_eq!(alloc.free(42, 4), Ok(()));
let expected = LinkedList::from_iter([
AllocatorNode::free(0, 40),
AllocatorNode::used(40, 42),
AllocatorNode::free(42, 46),
AllocatorNode::used(46, 56),
AllocatorNode::free(56, 128),
]);
itertools::assert_equal(alloc.ranges.iter(), expected.iter());
// Whole region free
assert_eq!(alloc.free(40, 2), Ok(()));
let expected = LinkedList::from_iter([
AllocatorNode::free(0, 46),
AllocatorNode::used(46, 56),
AllocatorNode::free(56, 128),
]);
itertools::assert_equal(alloc.ranges.iter(), expected.iter());
assert_eq!(alloc.free(46, 10), Ok(()));
let expected = LinkedList::from_iter([AllocatorNode::free(0, 128)]);
itertools::assert_equal(alloc.ranges.iter(), expected.iter());
}
#[test]
fn allocation() {
let ranges = LinkedList::from_iter([
AllocatorNode::free(0, 12),
AllocatorNode::used(12, 24),
AllocatorNode::free(24, 32),
AllocatorNode::used(32, 64),
]);
let mut alloc = TreeAllocator { ranges };
// Non-splitting allocation
assert_eq!(alloc.allocate(12), Some(0));
// Splitting allocation
assert_eq!(alloc.allocate(4), Some(24));
// Non-splitting allocation
assert_eq!(alloc.allocate(4), Some(28));
// Out of memory
assert_eq!(alloc.allocate(1), None);
let expected = LinkedList::from_iter([AllocatorNode::used(0, 64)]);
itertools::assert_equal(alloc.ranges, expected);
}
#[test]
fn insertion() {
let ranges = LinkedList::from_iter([
AllocatorNode::free(0, 12),
AllocatorNode::used(12, 24),
AllocatorNode::free(24, 32),
AllocatorNode::used(32, 64),
AllocatorNode::free(64, 128),
]);
let mut alloc = TreeAllocator { ranges };
// No split
assert_eq!(alloc.insert(0, 12), Ok(()));
let expected = LinkedList::from_iter([
AllocatorNode::used(0, 24),
AllocatorNode::free(24, 32),
AllocatorNode::used(32, 64),
AllocatorNode::free(64, 128),
]);
itertools::assert_equal(alloc.ranges.iter(), expected.iter());
// Split at the start
assert_eq!(alloc.insert(24, 4), Ok(()));
let expected = LinkedList::from_iter([
AllocatorNode::used(0, 28),
AllocatorNode::free(28, 32),
AllocatorNode::used(32, 64),
AllocatorNode::free(64, 128),
]);
itertools::assert_equal(alloc.ranges.iter(), expected.iter());
// Split at the end
assert_eq!(alloc.insert(30, 2), Ok(()));
let expected = LinkedList::from_iter([
AllocatorNode::used(0, 28),
AllocatorNode::free(28, 30),
AllocatorNode::used(30, 64),
AllocatorNode::free(64, 128),
]);
itertools::assert_equal(alloc.ranges.iter(), expected.iter());
// Split in the middle
assert_eq!(alloc.insert(72, 16), Ok(()));
let expected = LinkedList::from_iter([
AllocatorNode::used(0, 28),
AllocatorNode::free(28, 30),
AllocatorNode::used(30, 64),
AllocatorNode::free(64, 72),
AllocatorNode::used(72, 88),
AllocatorNode::free(88, 128),
]);
itertools::assert_equal(alloc.ranges.iter(), expected.iter());
}
}

64
lib/vmalloc/src/lib.rs Normal file
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@ -0,0 +1,64 @@
#![no_std]
#![feature(linked_list_cursors, let_chains, btree_extract_if)]
extern crate alloc;
use allocator::TreeAllocator;
use yggdrasil_abi::error::Error;
pub(crate) mod allocator;
#[derive(Debug, PartialEq, Eq, Clone, Copy)]
pub struct VirtualMemoryRange {
start_pfn: usize,
end_pfn: usize,
}
pub struct VirtualMemoryAllocator {
inner: TreeAllocator,
}
impl VirtualMemoryRange {
pub fn start_pfn(&self) -> usize {
self.start_pfn
}
pub fn end_pfn(&self) -> usize {
self.end_pfn
}
pub fn pfn_count(&self) -> usize {
self.end_pfn - self.start_pfn
}
pub fn contains(&self, other: &Self) -> bool {
other.start_pfn >= self.start_pfn && other.end_pfn <= self.end_pfn
}
}
impl VirtualMemoryAllocator {
pub fn new(start_pfn: usize, end_pfn: usize) -> Self {
Self {
inner: TreeAllocator::new(start_pfn, end_pfn),
}
}
pub fn allocate(&mut self, pfn_count: usize) -> Result<usize, Error> {
self.inner.allocate(pfn_count).ok_or(Error::OutOfMemory)
}
pub fn free(&mut self, start_pfn: usize, pfn_count: usize) -> Result<(), Error> {
self.inner.free(start_pfn, pfn_count)
}
pub fn insert(&mut self, start_pfn: usize, pfn_count: usize) -> Result<(), Error> {
self.inner.insert(start_pfn, pfn_count)
}
pub fn ranges(&self) -> impl Iterator<Item = (bool, VirtualMemoryRange)> + '_ {
self.inner.ranges()
}
}
#[cfg(test)]
mod tests {}

6
src/arch/mod.rs
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@ -27,10 +27,7 @@ use device_api::{
ResetDevice,
};
use crate::mem::{
device::RawDeviceMemoryMapping, phys::PhysicalMemoryRegion, table::KernelAddressSpace,
PhysicalAddress,
};
use crate::mem::{device::RawDeviceMemoryMapping, phys::PhysicalMemoryRegion, PhysicalAddress};
cfg_if! {
if #[cfg(target_arch = "aarch64")] {
@ -58,6 +55,7 @@ pub enum CpuMessage {
}
/// Interface for an architecture-specific facilities
#[allow(unused)]
pub trait Architecture {
/// Address, to which "zero" address is mapped in the virtual address space
const KERNEL_VIRT_OFFSET: usize;

12
src/arch/x86_64/acpi.rs
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@ -1,7 +1,6 @@
//! x86-64 implementation of ACPI management interfaces
use core::{
alloc::{AllocError, Allocator, GlobalAlloc, Layout},
mem::{align_of, size_of},
ptr::NonNull,
sync::atomic::Ordering,
time::Duration,
@ -89,17 +88,6 @@ impl acpi_system::Handler for AcpiHandlerImpl {
PhysicalAddress::from_raw(address),
length.try_into().unwrap(),
)
// PhysicalPointer::into_raw(slice)
// if address + length < 0x100000000 {
// core::slice::from_raw_parts(
// (address as usize).virtualize() as *const u8,
// length as usize,
// )
// } else {
// panic!("Unhandled address: {:#x}", address)
// }
}
fn io_read_u8(port: u16) -> u8 {

6
src/arch/x86_64/apic/ioapic.rs
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@ -16,11 +16,7 @@ use tock_registers::{
use crate::{
arch::x86_64::{acpi::AcpiAllocator, apic::local::BSP_APIC_ID, IrqNumber},
mem::{
address::FromRaw,
device::{DeviceMemoryIo, DeviceMemoryMapping},
PhysicalAddress,
},
mem::{address::FromRaw, device::DeviceMemoryIo, PhysicalAddress},
sync::IrqSafeSpinlock,
};

5
src/arch/x86_64/boot/mod.rs
View File

@ -8,10 +8,7 @@ use yboot_proto::{
};
use crate::{
arch::{
x86_64::{registers::MSR_IA32_KERNEL_GS_BASE, smp::CPU_COUNT},
ArchitectureImpl,
},
arch::x86_64::{registers::MSR_IA32_KERNEL_GS_BASE, smp::CPU_COUNT},
fs::devfs,
kernel_main, kernel_secondary_main,
mem::KERNEL_VIRT_OFFSET,

5
src/arch/x86_64/context.rs
View File

@ -90,8 +90,7 @@ impl TaskContextImpl for TaskContext {
fn kernel(entry: extern "C" fn(usize) -> !, arg: usize) -> Result<Self, Error> {
const KERNEL_TASK_PAGES: usize = 32;
let stack_base =
unsafe { phys::alloc_pages_contiguous(KERNEL_TASK_PAGES)?.virtualize_raw() };
let stack_base = phys::alloc_pages_contiguous(KERNEL_TASK_PAGES)?.virtualize_raw();
let mut stack = StackBuilder::new(stack_base, KERNEL_TASK_PAGES * 0x1000);
@ -123,7 +122,7 @@ impl TaskContextImpl for TaskContext {
) -> Result<Self, Error> {
const USER_TASK_PAGES: usize = 8;
let stack_base = unsafe { phys::alloc_pages_contiguous(USER_TASK_PAGES)?.virtualize_raw() };
let stack_base = phys::alloc_pages_contiguous(USER_TASK_PAGES)?.virtualize_raw();
let mut stack = StackBuilder::new(stack_base, USER_TASK_PAGES * 0x1000);

7
src/arch/x86_64/cpu.rs
View File

@ -7,12 +7,7 @@ use tock_registers::interfaces::Writeable;
use crate::{
arch::{
x86_64::{
cpuid::{self, PROCESSOR_FEATURES},
gdt,
registers::MSR_IA32_KERNEL_GS_BASE,
syscall,
},
x86_64::{cpuid, gdt, registers::MSR_IA32_KERNEL_GS_BASE, syscall},
CpuMessage,
},
sync::IrqSafeSpinlock,

6
src/arch/x86_64/mem/mod.rs
View File

@ -8,6 +8,7 @@ use kernel_util::util::OneTimeInit;
use memtables::FixedTables;
use static_assertions::{const_assert_eq, const_assert_ne};
pub mod process;
pub mod table;
use crate::{
@ -69,9 +70,6 @@ pub(super) const RAM_MAPPING_OFFSET: usize = CANONICAL_ADDRESS_MASK | (RAM_MAPPI
pub(super) static MEMORY_LIMIT: OneTimeInit<usize> = OneTimeInit::new();
pub(super) static mut RAM_MAPPING_L1: PageTable<L1> = PageTable::zeroed();
// Global limits
pub(super) const HEAP_SIZE_LIMIT: usize = L1::SIZE;
// Early mappings
unsafe fn map_early_pages(physical: PhysicalAddress, count: usize) -> Result<usize, Error> {
for l3i in 0..512 {
@ -189,8 +187,6 @@ pub(super) unsafe fn map_device_memory(
page_size: L2::SIZE,
})
} else {
let page_size = L3::SIZE;
// Just map the pages directly
let base_address = map_device_memory_l3(l3_aligned, page_count)?;
let address = base_address + l3_offset;

136
src/arch/x86_64/mem/process.rs Normal file
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@ -0,0 +1,136 @@
use yggdrasil_abi::error::Error;
use crate::{
arch::x86_64::intrinsics,
mem::{
address::AsPhysicalAddress,
phys,
pointer::PhysicalRefMut,
process::ProcessAddressSpaceManager,
table::{EntryLevel, MapAttributes, NextPageTable},
PhysicalAddress,
},
};
use super::{
clone_kernel_tables,
table::{PageEntry, PageTable, L0, L1, L2, L3},
};
/// Represents a process or kernel address space. Because x86-64 does not have cool stuff like
/// TTBR0 and TTBR1, all address spaces are initially cloned from the kernel space.
#[repr(C)]
pub struct ProcessAddressSpaceImpl {
l0: PhysicalRefMut<'static, PageTable<L0>>,
}
impl ProcessAddressSpaceManager for ProcessAddressSpaceImpl {
const PAGE_SIZE: usize = L3::SIZE;
const LOWER_LIMIT_PFN: usize = 8;
// 16GiB VM limit
const UPPER_LIMIT_PFN: usize = (16 << 30) / Self::PAGE_SIZE;
fn new() -> Result<Self, Error> {
let mut l0 = unsafe { PhysicalRefMut::<'static, PageTable<L0>>::map(phys::alloc_page()?) };
for i in 0..512 {
l0[i] = PageEntry::INVALID;
}
clone_kernel_tables(&mut *l0);
Ok(Self { l0 })
}
#[inline]
unsafe fn map_page(
&mut self,
address: usize,
physical: PhysicalAddress,
flags: MapAttributes,
) -> Result<(), Error> {
self.write_l3_entry(address, PageEntry::page(physical, flags.into()), false)
}
unsafe fn unmap_page(&mut self, address: usize) -> Result<PhysicalAddress, Error> {
self.pop_l3_entry(address)
}
#[inline]
fn translate(&self, address: usize) -> Result<(PhysicalAddress, MapAttributes), Error> {
self.read_l3_entry(address)
.ok_or(Error::InvalidMemoryOperation)
}
}
impl ProcessAddressSpaceImpl {
// Write a single 4KiB entry
fn write_l3_entry(
&mut self,
virt: usize,
entry: PageEntry<L3>,
overwrite: bool,
) -> Result<(), Error> {
let l0i = L0::index(virt);
let l1i = L1::index(virt);
let l2i = L2::index(virt);
let l3i = L3::index(virt);
let mut l1 = self.l0.get_mut_or_alloc(l0i)?;
let mut l2 = l1.get_mut_or_alloc(l1i)?;
let mut l3 = l2.get_mut_or_alloc(l2i)?;
if l3[l3i].is_present() && !overwrite {
todo!();
}
l3[l3i] = entry;
unsafe {
intrinsics::flush_tlb_entry(virt);
}
Ok(())
}
fn pop_l3_entry(&mut self, virt: usize) -> Result<PhysicalAddress, Error> {
let l0i = L0::index(virt);
let l1i = L1::index(virt);
let l2i = L2::index(virt);
let l3i = L3::index(virt);
// TODO somehow drop tables if they're known to be empty?
let mut l1 = self.l0.get_mut(l0i).ok_or(Error::DoesNotExist)?;
let mut l2 = l1.get_mut(l1i).ok_or(Error::DoesNotExist)?;
let mut l3 = l2.get_mut(l2i).ok_or(Error::DoesNotExist)?;
let page = l3[l3i].as_page().ok_or(Error::DoesNotExist)?;
l3[l3i] = PageEntry::INVALID;
unsafe {
intrinsics::flush_tlb_entry(virt);
}
Ok(page)
}
fn read_l3_entry(&self, virt: usize) -> Option<(PhysicalAddress, MapAttributes)> {
let l0i = L0::index(virt);
let l1i = L1::index(virt);
let l2i = L2::index(virt);
let l3i = L3::index(virt);
let l1 = self.l0.get(l0i)?;
let l2 = l1.get(l1i)?;
let l3 = l2.get(l2i)?;
let page = l3[l3i].as_page()?;
Some((page, l3[l3i].attributes().into()))
}
}
impl AsPhysicalAddress for ProcessAddressSpaceImpl {
unsafe fn as_physical_address(&self) -> PhysicalAddress {
self.l0.as_physical_address()
}
}

173
src/arch/x86_64/mem/table.rs
View File

@ -6,22 +6,14 @@ use core::{
use abi::error::Error;
use bitflags::bitflags;
use crate::{
arch::x86_64::intrinsics,
mem::{
address::{AsPhysicalAddress, FromRaw},
phys,
pointer::{PhysicalRef, PhysicalRefMut},
table::{
EntryLevel, MapAttributes, NextPageTable, NonTerminalEntryLevel, VirtualMemoryManager,
},
PhysicalAddress,
},
sync::IrqSafeSpinlock,
use crate::mem::{
address::{AsPhysicalAddress, FromRaw},
phys,
pointer::{PhysicalRef, PhysicalRefMut},
table::{EntryLevel, MapAttributes, NextPageTable, NonTerminalEntryLevel},
PhysicalAddress,
};
use super::{clone_kernel_tables, KERNEL_TABLES};
bitflags! {
/// Describes how each page table entry is mapped
pub struct PageAttributes: u64 {
@ -39,15 +31,8 @@ bitflags! {
}
}
/// Represents a process or kernel address space. Because x86-64 does not have cool stuff like
/// TTBR0 and TTBR1, all address spaces are initially cloned from the kernel space.
#[repr(C)]
pub struct AddressSpace {
inner: IrqSafeSpinlock<PhysicalRefMut<'static, PageTable<L0>>>,
}
/// Represents a single virtual address space mapping depending on its translation level
#[derive(Clone, Copy)]
#[derive(Clone, Copy, Debug)]
#[repr(transparent)]
pub struct PageEntry<L: EntryLevel>(u64, PhantomData<L>);
@ -59,16 +44,16 @@ pub struct PageTable<L: EntryLevel> {
}
/// Translation level 0 (PML4): Entry is 512GiB table
#[derive(Clone, Copy)]
#[derive(Clone, Copy, Debug)]
pub struct L0;
/// Translation level 1 (PDPT): Entry is 1GiB table
#[derive(Clone, Copy)]
#[derive(Clone, Copy, Debug)]
pub struct L1;
/// Translation level 2 (Page directory): Entry is 2MiB block/table
#[derive(Clone, Copy)]
#[derive(Clone, Copy, Debug)]
pub struct L2;
/// Translation level 3 (Page table): Entry is 4KiB page
#[derive(Clone, Copy)]
#[derive(Clone, Copy, Debug)]
pub struct L3;
impl NonTerminalEntryLevel for L0 {
@ -193,6 +178,10 @@ impl<L: NonTerminalEntryLevel> PageEntry<L> {
None
}
}
pub fn is_block(self) -> bool {
self.0 & PageAttributes::BLOCK.bits() != 0
}
}
impl<L: EntryLevel> PageEntry<L> {
@ -203,6 +192,10 @@ impl<L: EntryLevel> PageEntry<L> {
Self(raw, PhantomData)
}
pub fn attributes(&self) -> PageAttributes {
PageAttributes::from_bits_retain(self.0)
}
/// Returns `true` if the entry contains a valid mapping to either a table or to a page/block
pub fn is_present(&self) -> bool {
self.0 & PageAttributes::PRESENT.bits() != 0
@ -292,125 +285,17 @@ impl From<MapAttributes> for PageAttributes {
}
}
impl VirtualMemoryManager for AddressSpace {
fn allocate(
&self,
hint: Option<usize>,
len: usize,
attrs: MapAttributes,
) -> Result<usize, Error> {
if hint.is_some() {
todo!();
}
const TRY_ALLOC_START: usize = 0x100000000;
const TRY_ALLOC_END: usize = 0xF00000000;
'l0: for base in (TRY_ALLOC_START..TRY_ALLOC_END - len * 0x1000).step_by(0x1000) {
for i in 0..len {
if self.translate(base + i * 0x1000).is_some() {
continue 'l0;
}
}
for i in 0..len {
let page = phys::alloc_page()?;
self.map_page(base + i * 0x1000, page, attrs)?;
}
return Ok(base);
}
Err(Error::OutOfMemory)
}
fn map_page(
&self,
virt: usize,
phys: PhysicalAddress,
attrs: MapAttributes,
) -> Result<(), Error> {
self.write_entry(virt, PageEntry::page(phys, attrs.into()), true)
}
fn deallocate(&self, addr: usize, len: usize) -> Result<(), Error> {
for page in (addr..addr + len).step_by(0x1000) {
let Some(phys) = self.translate(page) else {
todo!();
};
self.write_entry(page, PageEntry::INVALID, true)?;
unsafe {
phys::free_page(phys);
impl From<PageAttributes> for MapAttributes {
fn from(value: PageAttributes) -> Self {
let mut res = MapAttributes::empty();
if value.contains(PageAttributes::USER) {
res |= MapAttributes::USER_READ;
if value.contains(PageAttributes::WRITABLE) {
res |= MapAttributes::USER_WRITE;
}
}
Ok(())
}
}
impl AddressSpace {
/// Allocates an empty address space with all entries marked as non-present
pub fn new_empty() -> Result<Self, Error> {
let mut l0 = unsafe { PhysicalRefMut::<'static, PageTable<L0>>::map(phys::alloc_page()?) };
for i in 0..512 {
unsafe {
l0[i] = PageEntry::INVALID;
}
}
clone_kernel_tables(&mut *l0);
Ok(Self {
inner: IrqSafeSpinlock::new(l0),
})
}
// TODO return page size and attributes
/// Returns the physical address to which the `virt` address is mapped
pub fn translate(&self, virt: usize) -> Option<PhysicalAddress> {
let l0 = self.inner.lock();
let l0i = L0::index(virt);
let l1i = L1::index(virt);
let l2i = L2::index(virt);
let l3i = L3::index(virt);
let l1 = l0.get(l0i)?;
let l2 = l1.get(l1i)?;
let l3 = l2.get(l2i)?;
l3[l3i].as_page()
}
// Write a single 4KiB entry
fn write_entry(&self, virt: usize, entry: PageEntry<L3>, overwrite: bool) -> Result<(), Error> {
let mut l0 = self.inner.lock();
let l0i = L0::index(virt);
let l1i = L1::index(virt);
let l2i = L2::index(virt);
let l3i = L3::index(virt);
let mut l1 = l0.get_mut_or_alloc(l0i)?;
let mut l2 = l1.get_mut_or_alloc(l1i)?;
let mut l3 = l2.get_mut_or_alloc(l2i)?;
if l3[l3i].is_present() && !overwrite {
todo!();
}
l3[l3i] = entry;
unsafe {
intrinsics::flush_tlb_entry(virt);
}
Ok(())
}
/// Returns the physical address of the root table
pub fn physical_address(&self) -> PhysicalAddress {
unsafe { self.inner.lock().as_physical_address() }
// TODO ???
res |= MapAttributes::NON_GLOBAL;
res
}
}

12
src/arch/x86_64/mod.rs
View File

@ -10,7 +10,6 @@ use device_api::{
};
use git_version::git_version;
use kernel_util::util::OneTimeInit;
use memtables::FixedTables;
use yboot_proto::{v1::AvailableMemoryRegion, LoadProtocolV1};
mod acpi;
@ -64,7 +63,7 @@ use self::{
mem::{
init_fixed_tables,
table::{PageAttributes, PageEntry, L1, L3},
EarlyMapping, KERNEL_TABLES, MEMORY_LIMIT, RAM_MAPPING_L1, RAM_MAPPING_OFFSET,
EarlyMapping, MEMORY_LIMIT, RAM_MAPPING_L1, RAM_MAPPING_OFFSET,
},
peripherals::{i8253::I8253, ps2::PS2Controller, serial::ComPort},
smp::CPU_COUNT,
@ -166,7 +165,7 @@ impl Architecture for X86_64 {
fn map_physical_memory<I: Iterator<Item = PhysicalMemoryRegion> + Clone>(
&self,
it: I,
_it: I,
_memory_start: PhysicalAddress,
memory_end: PhysicalAddress,
) -> Result<(), Error> {
@ -237,8 +236,9 @@ impl Architecture for X86_64 {
}
impl X86_64 {
unsafe fn handle_ipi(&self, msg: CpuMessage) {
todo!()
unsafe fn handle_ipi(&self, _msg: CpuMessage) {
warnln!("Received an IPI");
loop {}
}
fn set_boot_data(&self, data: BootData) {
@ -404,7 +404,7 @@ impl X86_64 {
self.ioapic.init(IoApic::from_acpi(&apic_info)?);
// acpi::init_acpi(acpi).unwrap();
acpi::init_acpi(acpi).unwrap();
if let Ok(mcfg) = acpi.find_table::<Mcfg>() {
for entry in mcfg.entries() {

4
src/arch/x86_64/smp.rs
View File

@ -9,7 +9,7 @@ use crate::{
boot::__x86_64_ap_entry,
intrinsics::flush_tlb_entry,
mem::{
table::{PageAttributes, L1, L2},
table::{PageAttributes, PageEntry, PageTable, L1, L2},
KERNEL_TABLES,
},
},
@ -19,7 +19,6 @@ use crate::{
address::{AsPhysicalAddress, FromRaw, IntoRaw},
phys,
pointer::PhysicalRefMut,
table::{PageEntry, PageTable},
PhysicalAddress,
},
task::Cpu,
@ -35,7 +34,6 @@ static AP_BOOTSTRAP_BIN: &[u8] = include_bytes!(concat!(env!("OUT_DIR"), "/__x86
const AP_STACK_PAGES: usize = 8;
const AP_BOOTSTRAP_DATA: PhysicalAddress = PhysicalAddress::from_raw(0x6000usize);
const AP_BOOTSTRAP_CODE: PhysicalAddress = PhysicalAddress::from_raw(0x7000usize);
const AP_ADDRESS_LIMIT: PhysicalAddress = PhysicalAddress::from_raw(0x100000usize);
#[repr(C)]
#[allow(dead_code)]

2
src/device/display/console.rs
View File

@ -3,7 +3,7 @@
use core::time::Duration;
use abi::{error::Error, primitive_enum};
use alloc::{boxed::Box, vec, vec::Vec};
use alloc::{vec, vec::Vec};
use bitflags::bitflags;
use kernel_util::util::StaticVector;

2
src/fs/mod.rs
View File

@ -7,7 +7,7 @@ use memfs::block::{self, BlockAllocator};
use vfs::VnodeRef;
use yggdrasil_abi::{error::Error, io::MountOptions};
use crate::mem::{self, phys, PhysicalAddress};
use crate::mem::{phys, PhysicalAddress};
pub mod devfs;

13
src/mem/address.rs
View File

@ -1,14 +1,11 @@
use core::{
fmt,
iter::Step,
marker::PhantomData,
mem::align_of,
ops::{Add, Deref, DerefMut, Sub},
};
use bytemuck::{Pod, Zeroable};
use crate::arch::{Architecture, ArchitectureImpl, ARCHITECTURE};
use crate::arch::{Architecture, ArchitectureImpl};
use super::{pointer::PhysicalPointer, table::EntryLevel, KERNEL_VIRT_OFFSET};
@ -185,16 +182,16 @@ impl From<PhysicalAddress> for usize {
// Ranges
impl Step for PhysicalAddress {
fn steps_between(start: &Self, end: &Self) -> Option<usize> {
loop {}
fn steps_between(_start: &Self, _end: &Self) -> Option<usize> {
todo!()
}
fn forward_checked(start: Self, count: usize) -> Option<Self> {
start.0.checked_add(count as u64).map(Self)
}
fn backward_checked(start: Self, count: usize) -> Option<Self> {
loop {}
fn backward_checked(_start: Self, _count: usize) -> Option<Self> {
todo!()
}
}

2
src/mem/heap.rs
View File

@ -35,7 +35,7 @@ unsafe impl GlobalAlloc for KernelAllocator {
match self.inner.lock().allocate_first_fit(layout) {
Ok(v) => v.as_ptr(),
Err(e) => {
// errorln!("Failed to allocate {:?}: {:?}", layout, e);
errorln!("Failed to allocate {:?}: {:?}", layout, e);
null_mut()
}
}

82
src/mem/mod.rs
View File

@ -1,25 +1,9 @@
// //! Memory management utilities and types
// // use core::{alloc::Layout, mem::size_of};
//
// use core::{alloc::Layout, ffi::c_void, mem::size_of};
//
// use abi::error::Error;
//
// // use abi::error::Error;
// //
// use crate::arch::{Architecture, ArchitectureImpl /*, PlatformImpl*/};
//
// use self::table::AddressSpace;
// //
// // use self::table::AddressSpace;
//
// pub mod device;
//! Memory management utilities and types
use core::{
alloc::Layout,
ffi::c_void,
mem::{align_of, size_of},
ops::Add,
};
use abi::error::Error;
@ -31,11 +15,12 @@ pub mod device;
pub mod heap;
pub mod phys;
pub mod pointer;
pub mod process;
pub mod table;
pub use address::PhysicalAddress;
use self::{device::DeviceMemoryMapping, table::AddressSpace};
use self::{device::DeviceMemoryMapping, process::ProcessAddressSpace};
pub const KERNEL_VIRT_OFFSET: usize = ArchitectureImpl::KERNEL_VIRT_OFFSET;
@ -60,42 +45,7 @@ pub unsafe fn write_memory<T>(address: PhysicalAddress, value: T) {
(address as *mut T).write_unaligned(value)
}
}
// pub mod phys;
//
// /// Kernel's physical load address
// // pub const KERNEL_PHYS_BASE: usize = PlatformImpl::KERNEL_PHYS_BASE;
// /// Kernel's virtual memory mapping offset (i.e. kernel's virtual address is [KERNEL_PHYS_BASE] +
// /// [KERNEL_VIRT_OFFSET])
// pub const KERNEL_VIRT_OFFSET: usize = ArchitectureImpl::KERNEL_VIRT_OFFSET;
//
// /// Interface for converting between address spaces.
// ///
// /// # Safety
// ///
// /// An incorrect implementation can produce invalid address.
// pub unsafe trait ConvertAddress {
// /// Convert the address into a virtual one
// ///
// /// # Panics
// ///
// /// Panics if the address is already a virtual one
// ///
// /// # Safety
// ///
// /// An incorrect implementation can produce invalid address.
// unsafe fn virtualize(self) -> Self;
// /// Convert the address into a physical one
// ///
// /// # Panics
// ///
// /// Panics if the address is already a physical one
// ///
// /// # Safety
// ///
// /// An incorrect implementation can produce invalid address.
// unsafe fn physicalize(self) -> Self;
// }
//
/// Helper trait to allow cross-address space access to pointers
pub trait ForeignPointer: Sized {
/// Perform a volatile pointer write without dropping the old value.
@ -111,7 +61,7 @@ pub trait ForeignPointer: Sized {
/// # Safety
///
/// As this function allows direct memory writes, it is inherently unsafe.
unsafe fn write_foreign_volatile(self: *mut Self, space: &AddressSpace, value: Self);
unsafe fn write_foreign_volatile(self: *mut Self, space: &ProcessAddressSpace, value: Self);
/// Performs pointer validation for given address space:
///
@ -125,7 +75,7 @@ pub trait ForeignPointer: Sized {
/// conversion, and thus is unsafe.
unsafe fn validate_user_ptr<'a>(
self: *const Self,
space: &AddressSpace,
space: &ProcessAddressSpace,
) -> Result<&'a Self, Error>;
/// [ForeignPointer::validate_user_ptr], with extra "writability" check.
@ -136,7 +86,7 @@ pub trait ForeignPointer: Sized {
/// conversion, and thus is unsafe.
unsafe fn validate_user_mut<'a>(
self: *mut Self,
space: &AddressSpace,
space: &ProcessAddressSpace,
) -> Result<&'a mut Self, Error>;
/// [ForeignPointer::validate_user_ptr], but for slices
@ -148,7 +98,7 @@ pub trait ForeignPointer: Sized {
unsafe fn validate_user_slice<'a>(
self: *const Self,
len: usize,
space: &AddressSpace,
space: &ProcessAddressSpace,
) -> Result<&'a [Self], Error>;
/// [ForeignPointer::validate_user_slice], but for mutable slices
@ -160,12 +110,12 @@ pub trait ForeignPointer: Sized {
unsafe fn validate_user_slice_mut<'a>(
self: *mut Self,
len: usize,
space: &AddressSpace,
space: &ProcessAddressSpace,
) -> Result<&'a mut [Self], Error>;
}
impl<T> ForeignPointer for T {
unsafe fn write_foreign_volatile(self: *mut Self, space: &AddressSpace, value: T) {
unsafe fn write_foreign_volatile(self: *mut Self, space: &ProcessAddressSpace, value: T) {
// TODO check align
let addr = self as usize;
let start_page = addr & !0xFFF;
@ -187,7 +137,7 @@ impl<T> ForeignPointer for T {
unsafe fn validate_user_slice_mut<'a>(
self: *mut Self,
len: usize,
space: &AddressSpace,
space: &ProcessAddressSpace,
) -> Result<&'a mut [Self], Error> {
let base = self as usize;
let layout = Layout::array::<T>(len).unwrap();
@ -201,7 +151,7 @@ impl<T> ForeignPointer for T {
unsafe fn validate_user_slice<'a>(
self: *const Self,
len: usize,
space: &AddressSpace,
space: &ProcessAddressSpace,
) -> Result<&'a [Self], Error> {
let base = self as usize;
let layout = Layout::array::<T>(len).unwrap();
@ -214,7 +164,7 @@ impl<T> ForeignPointer for T {
unsafe fn validate_user_mut<'a>(
self: *mut Self,
space: &AddressSpace,
space: &ProcessAddressSpace,
) -> Result<&'a mut Self, Error> {
let addr = self as usize;
let layout = Layout::new::<T>();
@ -231,7 +181,7 @@ impl<T> ForeignPointer for T {
unsafe fn validate_user_ptr<'a>(
self: *const Self,
space: &AddressSpace,
space: &ProcessAddressSpace,
) -> Result<&'a Self, Error> {
let addr = self as usize;
let layout = Layout::new::<T>();
@ -262,7 +212,7 @@ fn validate_user_align_size(addr: usize, layout: &Layout) -> Result<(), Error> {
/// Validates access to given userspace memory region with given constraints
pub fn validate_user_region(
space: &AddressSpace,
space: &ProcessAddressSpace,
base: usize,
len: usize,
_need_write: bool,
@ -276,7 +226,7 @@ pub fn validate_user_region(
for page in (aligned_start..aligned_end).step_by(0x1000) {
// TODO check writability
space.translate(page).ok_or(Error::InvalidArgument)?;
space.translate(page)?;
}
Ok(())

4
src/mem/phys/manager.rs
View File

@ -30,10 +30,8 @@ impl PhysicalMemoryManager {
bitmap_phys_base: PhysicalAddress,
page_count: usize,
) -> PhysicalMemoryManager {
// let bitmap_addr = bitmap_phys_base.virtualize();
let bitmap_len = (page_count + (BITMAP_WORD_SIZE - 1)) / BITMAP_WORD_SIZE;
let mut bitmap = PhysicalRefMut::<'static, u64>::map_slice(bitmap_phys_base, bitmap_len);
// let bitmap = core::slice::from_raw_parts_mut(bitmap_addr as *mut BitmapWord, bitmap_len);
bitmap.fill(BitmapWord::MAX);
@ -85,7 +83,7 @@ impl PhysicalMemoryManager {
'l0: for i in (aligned_bit..self.page_count).step_by(512) {
for j in 0..HUGE_PAGE_WORD_COUNT {
if self.bitmap[i / BITMAP_WORD_SIZE] != 0 {
if self.bitmap[i / BITMAP_WORD_SIZE + j] != 0 {
continue 'l0;
}
}

150
src/mem/phys/mod.rs
View File

@ -1,4 +1,4 @@
use core::{iter::StepBy, ops::Range};
use core::ops::Range;
use abi::error::Error;
use kernel_util::util::OneTimeInit;
@ -10,68 +10,18 @@ use crate::{
};
use self::{
manager::{PhysicalMemoryManager, BITMAP_PAGE_COUNT, BITMAP_WORD_SIZE, TRACKED_PAGE_LIMIT},
manager::{PhysicalMemoryManager, BITMAP_WORD_SIZE, TRACKED_PAGE_LIMIT},
reserved::reserve_region,
};
use super::{address::FromRaw, PhysicalAddress};
// //! Physical memory management facilities
// use core::{iter::StepBy, mem::size_of, ops::Range};
//
// use abi::error::Error;
// use kernel_util::util::OneTimeInit;
//
// use crate::{
// debug::LogLevel,
// mem::{
// phys::reserved::{is_reserved, reserve_region},
// ConvertAddress, /*, KERNEL_PHYS_BASE */
// },
// sync::IrqSafeSpinlock,
// };
//
// use self::manager::PhysicalMemoryManager;
//
// // Enumerating lots of pages is slow and I'm too lazy right now to write a better algorithm, so
// // capping the page count helps
// const PHYS_MEMORY_PAGE_CAP: usize = 65536;
//
// 8 * 4096 bits per page, 1 page per bit
const MEMORY_UPPER_LIMIT: PhysicalAddress = PhysicalAddress::from_raw(TRACKED_PAGE_LIMIT * 4096);
mod manager;
pub mod reserved;
//
// /// Contains information about the physical memory usage
// #[derive(Clone, Copy, Debug)]
// pub struct PhysicalMemoryStats {
// /// Number of pages available for allocation
// pub available_pages: usize,
// /// Number of pages being used
// pub used_pages: usize,
// }
//
// /// Represents the way in which the page is used (or not)
// #[derive(PartialEq, Clone, Copy, Debug)]
// #[repr(u32)]
// pub enum PageUsage {
// /// Page is not available for allocation or use
// Reserved = 0,
// /// Regular page available for allocation
// Available,
// /// Page is used by some kernel facility
// Used,
// }
//
// /// Page descriptor structure for the page management array
// #[repr(C)]
// pub struct Page {
// usage: PageUsage,
// refcount: u32,
// }
//
/// Defines an usable memory region
#[derive(Clone, Copy, Debug)]
pub struct PhysicalMemoryRegion {
@ -103,46 +53,7 @@ impl PhysicalMemoryRegion {
}
}
}
//
// impl PhysicalMemoryStats {
// /// Handles "alloc" cases of the memory manager
// pub fn add_allocated_pages(&mut self, count: usize, _usage: PageUsage) {
// assert!(self.available_pages >= count);
// self.available_pages -= count;
// self.used_pages += count;
// }
//
// /// Handles "free" cases of the memory manager
// pub fn add_freed_pages(&mut self, count: usize, _usage: PageUsage) {
// assert!(self.used_pages >= count);
// self.used_pages -= count;
// self.available_pages += count;
// }
//
// /// Increases the available pages counter
// pub fn add_available_pages(&mut self, count: usize) {
// self.available_pages += count;
// }
//
// /// Prints out the statistics into specified log level
// pub fn dump(&self, level: LogLevel) {
// log_print_raw!(level, "+++ Physical memory stats +++\n");
// log_print_raw!(
// level,
// "Available: {}K ({} pages)\n",
// self.available_pages * 4,
// self.available_pages
// );
// log_print_raw!(
// level,
// "Used: {}K ({} pages)\n",
// self.used_pages * 4,
// self.used_pages
// );
// log_print_raw!(level, "-----------------------------\n");
// }
// }
//
/// Global physical memory manager
pub static PHYSICAL_MEMORY: OneTimeInit<IrqSafeSpinlock<PhysicalMemoryManager>> =
OneTimeInit::new();
@ -267,58 +178,7 @@ pub unsafe fn init_from_iter<I: Iterator<Item = PhysicalMemoryRegion> + Clone>(
Ok(())
}
//
// debugln!("Initializing physical memory manager");
// debugln!("Total tracked pages: {}", total_count);
//
// // Reserve memory regions from which allocation is forbidden
// reserve_region("kernel", kernel_physical_memory_region());
//
// let pages_array_base = find_contiguous_region(it.clone(), (pages_array_size + 0xFFF) / 0x1000)
// .ok_or(Error::OutOfMemory)?;
//
// debugln!(
// "Placing page tracking at {:#x}",
// pages_array_base.virtualize()
// );
//
// reserve_region(
// "pages",
// PhysicalMemoryRegion {
// base: pages_array_base,
// size: (pages_array_size + 0xFFF) & !0xFFF,
// },
// );
//
// let mut manager =
// PhysicalMemoryManager::new(phys_start, pages_array_base.virtualize(), pages_array_size);
// let mut page_count = 0;
//
// for region in it {
// if page_count >= PHYS_MEMORY_PAGE_CAP {
// break;
// }
//
// for page in region.pages() {
// if is_reserved(page) {
// continue;
// }
//
// manager.add_available_page(page);
// page_count += 1;
//
// if page_count >= PHYS_MEMORY_PAGE_CAP {
// break;
// }
// }
// }
//
// infoln!("{} available pages ({}KiB)", page_count, page_count * 4);
//
// PHYSICAL_MEMORY.init(IrqSafeSpinlock::new(manager));
// Ok(())
// }
//
fn kernel_physical_memory_region() -> PhysicalMemoryRegion {
extern "C" {
static __kernel_phys_start: u8;

9
src/mem/phys/reserved.rs
View File

@ -13,14 +13,7 @@ static mut RESERVED_MEMORY: StaticVector<PhysicalMemoryRegion, 8> = StaticVector
/// # Safety
///
/// Can only be called from initialization code **before** physical memory manager is initialized.
pub unsafe fn reserve_region(reason: &str, region: PhysicalMemoryRegion) {
// debugln!(
// "Reserve {:?} memory: {:#x}..{:#x}",
// reason,
// region.base,
// region.end()
// );
pub unsafe fn reserve_region(_reason: &str, region: PhysicalMemoryRegion) {
RESERVED_MEMORY.push(region);
}

1
src/mem/pointer.rs
View File

@ -1,5 +1,4 @@
use core::{
alloc::Layout,
fmt,
mem::align_of,
ops::{Deref, DerefMut},

232
src/mem/process.rs Normal file
View File

@ -0,0 +1,232 @@
use abi::error::Error;
use cfg_if::cfg_if;
use vmalloc::VirtualMemoryAllocator;
use crate::{arch::x86_64::mem::table::L3, mem::phys, sync::IrqSafeSpinlock};
use super::{address::AsPhysicalAddress, table::MapAttributes, PhysicalAddress};
cfg_if! {
if #[cfg(target_arch = "aarch64")] {
use crate::arch::aarch64::table::AddressSpace;
} else if #[cfg(target_arch = "x86_64")] {
use crate::arch::x86_64::mem::process::ProcessAddressSpaceImpl;
}
}
/// Interface for virtual memory address space management
pub trait ProcessAddressSpaceManager: Sized + AsPhysicalAddress {
const PAGE_SIZE: usize;
const LOWER_LIMIT_PFN: usize;
const UPPER_LIMIT_PFN: usize;
fn new() -> Result<Self, Error>;
unsafe fn map_page(
&mut self,
address: usize,
physical: PhysicalAddress,
flags: MapAttributes,
) -> Result<(), Error>;
unsafe fn unmap_page(&mut self, address: usize) -> Result<PhysicalAddress, Error>;
fn translate(&self, address: usize) -> Result<(PhysicalAddress, MapAttributes), Error>;
}
struct Inner {
allocator: VirtualMemoryAllocator,
table: ProcessAddressSpaceImpl,
}
pub struct ProcessAddressSpace {
inner: IrqSafeSpinlock<Inner>,
}
impl Inner {
fn try_map_pages<F: Fn(usize) -> Result<PhysicalAddress, Error>>(
&mut self,
address: usize,
page_count: usize,
get_page: F,
attributes: MapAttributes,
) -> Result<(), (usize, Error)> {
for i in 0..page_count {
let virt = address + i * ProcessAddressSpaceImpl::PAGE_SIZE;
let phys = match get_page(virt) {
Ok(page) => page,
Err(err) => {
return Err((i, err));
}
};
if let Err(err) = unsafe { self.table.map_page(virt, phys, attributes) } {
return Err((i, err));
}
}
Ok(())
}
fn map_range<F: Fn(usize) -> Result<PhysicalAddress, Error>>(
&mut self,
address: usize,
page_count: usize,
get_page: F,
attributes: MapAttributes,
) -> Result<(), Error> {
// If inserting fails, the range cannot be mapped
let start_pfn = address / ProcessAddressSpaceImpl::PAGE_SIZE;
self.allocator.insert(start_pfn, page_count)?;
if let Err(_e) = self.try_map_pages(address, page_count, get_page, attributes) {
// TODO rollback & remove the range
todo!();
};
Ok(())
}
fn alloc_range<F: Fn(usize) -> Result<PhysicalAddress, Error>>(
&mut self,
page_count: usize,
get_page: F,
attributes: MapAttributes,
) -> Result<usize, Error> {
let start_pfn = self.allocator.allocate(page_count)?;
let address = start_pfn * ProcessAddressSpaceImpl::PAGE_SIZE;
if let Err(_e) = self.try_map_pages(address, page_count, get_page, attributes) {
// TODO rollback
todo!();
};
Ok(address)
}
unsafe fn unmap_range<F: Fn(usize, PhysicalAddress)>(
&mut self,
start_address: usize,
page_count: usize,
free_page: F,
) -> Result<(), Error> {
let start_pfn = start_address / ProcessAddressSpaceImpl::PAGE_SIZE;
// Deallocate the range first
self.allocator.free(start_pfn, page_count)?;
// Then unmap it from the table
for i in 0..page_count {
let virt = start_address + i * ProcessAddressSpaceImpl::PAGE_SIZE;
// This should not fail under normal circumstances
// TODO handle failures here?
let phys = self.table.unmap_page(virt).unwrap();
free_page(virt, phys);
}
Ok(())
}
}
impl ProcessAddressSpace {
pub fn new() -> Result<Self, Error> {
let table = ProcessAddressSpaceImpl::new()?;
let allocator = VirtualMemoryAllocator::new(
ProcessAddressSpaceImpl::LOWER_LIMIT_PFN,
ProcessAddressSpaceImpl::UPPER_LIMIT_PFN,
);
Ok(Self {
inner: IrqSafeSpinlock::new(Inner { table, allocator }),
})
}
pub fn allocate<F: Fn(usize) -> Result<PhysicalAddress, Error>>(
&self,
_hint: Option<usize>,
size: usize,
get_page: F,
attributes: MapAttributes,
) -> Result<usize, Error> {
assert_eq!(size & (ProcessAddressSpaceImpl::PAGE_SIZE - 1), 0);
let mut lock = self.inner.lock();
lock.alloc_range(
size / ProcessAddressSpaceImpl::PAGE_SIZE,
get_page,
attributes,
)
}
pub fn map<F: Fn(usize) -> Result<PhysicalAddress, Error>>(
&self,
address: usize,
size: usize,
get_page: F,
attributes: MapAttributes,
) -> Result<(), Error> {
assert_eq!(address & (ProcessAddressSpaceImpl::PAGE_SIZE - 1), 0);
assert_eq!(size & (ProcessAddressSpaceImpl::PAGE_SIZE - 1), 0);
let mut lock = self.inner.lock();
lock.map_range(
address,
size / ProcessAddressSpaceImpl::PAGE_SIZE,
get_page,
attributes,
)
}
pub fn map_single(
&self,
address: usize,
physical: PhysicalAddress,
attributes: MapAttributes,
) -> Result<(), Error> {
assert_eq!(address & (ProcessAddressSpaceImpl::PAGE_SIZE - 1), 0);
assert!(physical.is_aligned_for::<L3>());
self.inner
.lock()
.map_range(address, 1, |_| Ok(physical), attributes)
}
pub fn translate(&self, address: usize) -> Result<PhysicalAddress, Error> {
// Offset is handled at impl level
self.inner.lock().table.translate(address).map(|e| e.0)
}
pub unsafe fn unmap(&self, address: usize, size: usize) -> Result<(), Error> {
assert_eq!(address & (ProcessAddressSpaceImpl::PAGE_SIZE - 1), 0);
assert_eq!(size & (ProcessAddressSpaceImpl::PAGE_SIZE - 1), 0);
let mut lock = self.inner.lock();
lock.unmap_range(
address,
size / ProcessAddressSpaceImpl::PAGE_SIZE,
|_, paddr| phys::free_page(paddr),
)
}
pub fn debug_dump(&self) {
let lock = self.inner.lock();
debugln!("Address space @ {:#x}", unsafe {
lock.table.as_physical_address()
});
for (used, range) in lock.allocator.ranges() {
let start = range.start_pfn() * ProcessAddressSpaceImpl::PAGE_SIZE;
let end = range.end_pfn() * ProcessAddressSpaceImpl::PAGE_SIZE;
debugln!("{:#x?}: {}", start..end, used);
}
}
}
impl AsPhysicalAddress for ProcessAddressSpace {
unsafe fn as_physical_address(&self) -> PhysicalAddress {
self.inner.lock().table.as_physical_address()
}
}

45
src/mem/table.rs
View File

@ -3,17 +3,6 @@ use core::ops::{Deref, DerefMut};
use abi::error::Error;
use bitflags::bitflags;
use cfg_if::cfg_if;
use super::PhysicalAddress;
cfg_if! {
if #[cfg(target_arch = "aarch64")] {
pub use crate::arch::aarch64::table::{AddressSpace, PageAttributes, PageEntry, PageTable};
} else if #[cfg(target_arch = "x86_64")] {
pub use crate::arch::x86_64::mem::table::{AddressSpace, PageEntry, PageTable};
}
}
bitflags! {
/// Describes how a page translation mapping should behave
@ -28,40 +17,6 @@ bitflags! {
}
}
/// Interface for virtual memory address space management
pub trait VirtualMemoryManager {
/// Allocates a region of virtual memory inside the address space and maps it to physical
/// memory pages with given attributes
fn allocate(
&self,
hint: Option<usize>,
len: usize,
attrs: MapAttributes,
) -> Result<usize, Error>;
/// Insert a single 4KiB-page translation mapping into the table
fn map_page(
&self,
virt: usize,
phys: PhysicalAddress,
attrs: MapAttributes,
) -> Result<(), Error>;
/// Releases the virtual memory region from the address space and the pages it refers to
fn deallocate(&self, addr: usize, len: usize) -> Result<(), Error>;
}
pub trait KernelAddressSpace {
type Mapping;
fn map_page(
&self,
virt: usize,
physical: PhysicalAddress,
attrs: MapAttributes,
) -> Result<Self::Mapping, Error>;
}
/// Interface for non-terminal tables to retrieve the next level of address translation tables
pub trait NextPageTable {
/// Type for the next-level page table

59
src/proc/elf.rs
View File

@ -10,9 +10,7 @@ use vfs::{FileRef, Read, Seek};
use yggdrasil_abi::{error::Error, io::SeekFrom};
use crate::mem::{
phys,
pointer::PhysicalRefMut,
table::{AddressSpace, MapAttributes, VirtualMemoryManager},
phys, pointer::PhysicalRefMut, process::ProcessAddressSpace, table::MapAttributes,
};
#[derive(Clone, Copy)]
@ -59,24 +57,16 @@ fn from_parse_error(v: ParseError) -> Error {
}
fn load_bytes<F>(
space: &AddressSpace,
space: &ProcessAddressSpace,
addr: usize,
mut src: F,
len: usize,
elf_attrs: u32,
) -> Result<(), Error>
where
F: FnMut(usize, PhysicalRefMut<'_, [u8]>) -> Result<(), Error>,
{
// TODO check for crazy addresses here
let attrs = match (elf_attrs & PF_W, elf_attrs & PF_X) {
(0, 0) => MapAttributes::USER_READ,
(_, 0) => MapAttributes::USER_WRITE | MapAttributes::USER_READ,
(0, _) => MapAttributes::USER_READ,
(_, _) => MapAttributes::USER_WRITE | MapAttributes::USER_READ,
} | MapAttributes::NON_GLOBAL;
let dst_page_off = addr & 0xFFF;
let dst_page_aligned = addr & !0xFFF;
let mut off = 0usize;
@ -89,22 +79,9 @@ where
let virt_page = dst_page_aligned + page_idx * 0x1000;
assert_eq!(virt_page & 0xFFF, 0);
if let Some(page) = space.translate(virt_page) {
// TODO Handle these cases
warnln!("Page {:#x} is already mapped to {:#x}", virt_page, page);
todo!();
}
let phys_page = phys::alloc_page()?;
space.map_page(virt_page, phys_page, attrs)?;
// debugln!("Map {:#x} -> {:#x}", virt_page, phys_page);
let phys_page = space.translate(virt_page)?;
let dst_slice = unsafe { PhysicalRefMut::map_slice(phys_page.add(page_off), count) };
// let dst_slice = unsafe {
// let addr = (phys_page + page_off).virtualize();
// core::slice::from_raw_parts_mut(addr as *mut u8, count)
// };
src(off, dst_slice)?;
@ -116,17 +93,41 @@ where
}
/// Loads an ELF binary from `file` into the target address space
pub fn load_elf_from_file(space: &AddressSpace, file: FileRef) -> Result<usize, Error> {
pub fn load_elf_from_file(space: &ProcessAddressSpace, file: FileRef) -> Result<usize, Error> {
let file = FileReader { file: &file };
let elf = ElfStream::<AnyEndian, _>::open_stream(file).map_err(from_parse_error)?;
space.debug_dump();
for phdr in elf.segments() {
if phdr.p_type != PT_LOAD {
continue;
}
debugln!("LOAD {:#x}", phdr.p_vaddr);
debugln!("LOAD {:#x?}", phdr.p_vaddr..phdr.p_vaddr + phdr.p_memsz);
let attrs = match (phdr.p_flags & PF_W, phdr.p_flags & PF_X) {
(0, 0) => MapAttributes::USER_READ,
(_, 0) => MapAttributes::USER_WRITE | MapAttributes::USER_READ,
(0, _) => MapAttributes::USER_READ,
(_, _) => MapAttributes::USER_WRITE | MapAttributes::USER_READ,
} | MapAttributes::NON_GLOBAL;
if phdr.p_memsz > 0 {
// Map the range
let aligned_start = (phdr.p_vaddr as usize) & !0xFFF;
let aligned_end = ((phdr.p_vaddr + phdr.p_memsz) as usize + 0xFFF) & !0xFFF;
space.map(
aligned_start,
aligned_end - aligned_start,
|_| phys::alloc_page(),
attrs,
)?;
} else {
continue;
}
if phdr.p_filesz > 0 {
load_bytes(
@ -138,7 +139,6 @@ pub fn load_elf_from_file(space: &AddressSpace, file: FileRef) -> Result<usize,
source.read_exact(dst.deref_mut())
},
phdr.p_filesz as usize,
phdr.p_flags,
)?;
}
@ -154,7 +154,6 @@ pub fn load_elf_from_file(space: &AddressSpace, file: FileRef) -> Result<usize,
Ok(())
},
len,
phdr.p_flags,
)?;
}
}

35
src/proc/exec.rs
View File

@ -7,15 +7,14 @@ use vfs::FileRef;
use crate::{
mem::{
phys,
table::{AddressSpace, MapAttributes, VirtualMemoryManager},
address::AsPhysicalAddress, phys, process::ProcessAddressSpace, table::MapAttributes,
ForeignPointer,
},
proc,
task::{context::TaskContextImpl, process::Process, TaskContext},
};
fn setup_args(space: &AddressSpace, virt: usize, args: &[&str]) -> Result<(), Error> {
fn setup_args(space: &ProcessAddressSpace, virt: usize, args: &[&str]) -> Result<(), Error> {
// arg data len
let args_size: usize = args.iter().map(|x| x.len()).sum();
// 1 + arg ptr:len count
@ -30,13 +29,11 @@ fn setup_args(space: &AddressSpace, virt: usize, args: &[&str]) -> Result<(), Er
debugln!("arg data size = {}", args_size);
let phys_page = phys::alloc_page()?;
// TODO check if this doesn't overwrite anything
space.map_page(
space.map_single(
virt,
phys_page,
MapAttributes::USER_READ | MapAttributes::USER_WRITE | MapAttributes::NON_GLOBAL,
)?;
let write = phys_page.virtualize_raw();
let mut offset = args_ptr_size;
@ -57,6 +54,7 @@ fn setup_args(space: &AddressSpace, virt: usize, args: &[&str]) -> Result<(), Er
}
// Place the argument data
// TODO rewrite using write_foreign
unsafe {
let arg_data_slice =
core::slice::from_raw_parts_mut((write + args_ptr_size) as *mut u8, args_size);
@ -72,7 +70,7 @@ fn setup_args(space: &AddressSpace, virt: usize, args: &[&str]) -> Result<(), Er
fn setup_binary<S: Into<String>>(
name: S,
space: AddressSpace,
space: ProcessAddressSpace,
entry: usize,
args: &[&str],
) -> Result<Arc<Process>, Error> {
@ -82,14 +80,12 @@ fn setup_binary<S: Into<String>>(
// 0x1000 of guard page
let virt_args_base = virt_stack_base + (USER_STACK_PAGES + 1) * 0x1000;
for i in 0..USER_STACK_PAGES {
let phys = phys::alloc_page()?;
space.map_page(
virt_stack_base + i * 0x1000,
phys,
MapAttributes::USER_WRITE | MapAttributes::USER_READ | MapAttributes::NON_GLOBAL,
)?;
}
space.map(
virt_stack_base,
USER_STACK_PAGES * 0x1000,
|_| phys::alloc_page(),
MapAttributes::USER_WRITE | MapAttributes::USER_READ | MapAttributes::NON_GLOBAL,
)?;
setup_args(&space, virt_args_base, args)?;
@ -113,7 +109,12 @@ fn setup_binary<S: Into<String>>(
}
}
let context = TaskContext::user(entry, virt_args_base, space.physical_address(), user_sp)?;
let context = TaskContext::user(
entry,
virt_args_base,
unsafe { space.as_physical_address() },
user_sp,
)?;
Ok(Process::new_with_context(name, Some(space), context))
}
@ -124,7 +125,7 @@ pub fn load_elf<S: Into<String>>(
file: FileRef,
args: &[&str],
) -> Result<Arc<Process>, Error> {
let space = AddressSpace::new_empty()?;
let space = ProcessAddressSpace::new()?;
let elf_entry = proc::elf::load_elf_from_file(&space, file)?;
setup_binary(name, space, elf_entry, args)

17
src/syscall/mod.rs
View File

@ -16,7 +16,7 @@ use yggdrasil_abi::{
use crate::{
block, fs,
mem::table::{MapAttributes, VirtualMemoryManager},
mem::{phys, table::MapAttributes},
proc::{self, io::ProcessIo},
sync::IrqSafeSpinlockGuard,
task::{process::Process, runtime, ProcessId},
@ -82,11 +82,14 @@ fn syscall_handler(func: SyscallFunction, args: &[u64]) -> Result<usize, Error>
todo!();
}
space.allocate(
let res = space.allocate(
None,
len / 0x1000,
MapAttributes::USER_READ | MapAttributes::USER_WRITE | MapAttributes::NON_GLOBAL,
)
len,
|_| phys::alloc_page(),
MapAttributes::USER_WRITE | MapAttributes::USER_READ | MapAttributes::NON_GLOBAL,
);
res
}
SyscallFunction::UnmapMemory => {
let addr = args[0] as usize;
@ -99,7 +102,9 @@ fn syscall_handler(func: SyscallFunction, args: &[u64]) -> Result<usize, Error>
todo!();
}
space.deallocate(addr, len)?;
unsafe {
space.unmap(addr, len)?;
}
Ok(0)
}

11
src/task/process.rs
View File

@ -18,8 +18,7 @@ use kernel_util::util::OneTimeInit;
use vfs::VnodeRef;
use crate::{
arch::{Architecture, ArchitectureImpl},
mem::{table::AddressSpace, ForeignPointer},
mem::{process::ProcessAddressSpace, ForeignPointer},
proc::io::ProcessIo,
sync::{IrqGuard, IrqSafeSpinlock},
task::context::TaskContextImpl,
@ -72,7 +71,7 @@ pub struct Process {
id: OneTimeInit<ProcessId>,
state: AtomicProcessState,
cpu_id: AtomicU32,
space: Option<AddressSpace>,
space: Option<ProcessAddressSpace>,
inner: IrqSafeSpinlock<ProcessInner>,
exit_waker: QueueWaker,
@ -92,7 +91,7 @@ impl Process {
/// Has side-effect of allocating a new PID for itself.
pub fn new_with_context<S: Into<String>>(
name: S,
space: Option<AddressSpace>,
space: Option<ProcessAddressSpace>,
normal_context: TaskContext,
) -> Arc<Self> {
let this = Arc::new(Self {
@ -172,12 +171,12 @@ impl Process {
}
/// Returns the address space of the task
pub fn address_space(&self) -> &AddressSpace {
pub fn address_space(&self) -> &ProcessAddressSpace {
self.space.as_ref().unwrap()
}
/// Returns the address space of the task, if one is set
pub fn get_address_space(&self) -> Option<&AddressSpace> {
pub fn get_address_space(&self) -> Option<&ProcessAddressSpace> {
self.space.as_ref()
}