ClawSeven commented on code in PR #436: URL: https://github.com/apache/incubator-teaclave-sgx-sdk/pull/436#discussion_r1410328465
########## sgx_trts/src/emm/alloc.rs: ########## @@ -0,0 +1,542 @@ +// Licensed to the Apache Software Foundation (ASF) under one +// or more contributor license agreements. See the NOTICE file +// distributed with this work for additional information +// regarding copyright ownership. The ASF licenses this file +// to you under the Apache License, Version 2.0 (the +// "License"); you may not use this file except in compliance +// with the License. You may obtain a copy of the License at +// +// http://www.apache.org/licenses/LICENSE-2.0 +// +// Unless required by applicable law or agreed to in writing, +// software distributed under the License is distributed on an +// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY +// KIND, either express or implied. See the License for the +// specific language governing permissions and limitations +// under the License.. + +use buddy_system_allocator::LockedHeap; +use intrusive_collections::intrusive_adapter; +use intrusive_collections::singly_linked_list::CursorMut; +use intrusive_collections::singly_linked_list::{Link, SinglyLinkedList}; +use intrusive_collections::UnsafeRef; +use sgx_tlibc_sys::ENOMEM; + +use core::alloc::{AllocError, Allocator, Layout}; +use core::mem::size_of; +use core::mem::transmute; +use core::mem::MaybeUninit; +use core::ptr::NonNull; +use spin::{Mutex, Once}; + +use super::ema::EmaOptions; +use super::page::AllocFlags; +use super::vmmgr::{RangeType, VMMGR}; +use super::{PageInfo, PageType, ProtFlags}; +use sgx_types::error::OsResult; + +// The size of fixed static memory for Static Allocator +const STATIC_MEM_SIZE: usize = 65536; + +// The size of initial reserve memory for Reserve Allocator +const INIT_MEM_SIZE: usize = 65536; + +// The size of guard pages +const GUARD_SIZE: usize = 0x8000; + +// The max allocated size of Reserve Allocator +const MAX_EMALLOC_SIZE: usize = 0x10000000; + +const ALLOC_MASK: usize = 1; +const SIZE_MASK: usize = !(EXACT_MATCH_INCREMENT - 1); + +/// Static memory for allocation +static mut STATIC_MEM: [u8; STATIC_MEM_SIZE] = [0; STATIC_MEM_SIZE]; + +/// Lowest level: Allocator for static memory +/// +/// TODO: reimplement static allocator with monotone increasing policies +static STATIC: Once<LockedHeap<32>> = Once::new(); + +/// Second level: Allocator for reserve memory +static RSRV_ALLOCATOR: Once<Mutex<Reserve>> = Once::new(); + +/// Init lowest level static memory allocator +pub fn init_static_alloc() { + STATIC.call_once(|| { + let static_alloc = LockedHeap::empty(); + unsafe { + static_alloc + .lock() + .init(STATIC_MEM.as_ptr() as usize, STATIC_MEM_SIZE) + }; + static_alloc + }); +} + +/// Init reserve memory allocator +/// init_reserve_alloc() need to be called after init_static_alloc() +pub fn init_reserve_alloc() { + RSRV_ALLOCATOR.call_once(|| Mutex::new(Reserve::new(INIT_MEM_SIZE))); +} + +/// AllocType layout memory from reserve memory region +#[derive(Clone, Copy, Debug, PartialEq, Eq)] +pub struct RsrvAlloc; + +unsafe impl Allocator for RsrvAlloc { + fn allocate(&self, layout: Layout) -> Result<NonNull<[u8]>, AllocError> { + let size = layout.size(); + RSRV_ALLOCATOR + .get() + .unwrap() + .lock() + .emalloc(size) + .map(|addr| NonNull::slice_from_raw_parts(NonNull::new(addr as *mut u8).unwrap(), size)) + .map_err(|_| AllocError) + } + + #[inline] + unsafe fn deallocate(&self, ptr: NonNull<u8>, _layout: Layout) { + RSRV_ALLOCATOR.get().unwrap().lock().efree(ptr.addr().get()) + } +} + +/// AllocType layout memory from static memory region +#[derive(Clone, Copy, Debug, PartialEq, Eq)] +pub struct StaticAlloc; + +unsafe impl Allocator for StaticAlloc { + fn allocate(&self, layout: Layout) -> Result<NonNull<[u8]>, AllocError> { + STATIC + .get() + .unwrap() + .lock() + .alloc(layout) + .map(|addr| NonNull::slice_from_raw_parts(addr, layout.size())) + .map_err(|_| AllocError) + } + + #[inline] + unsafe fn deallocate(&self, ptr: NonNull<u8>, layout: Layout) { + STATIC.get().unwrap().lock().dealloc(ptr, layout); + } +} + +// Enum for allocator types +#[derive(Clone, Copy, Debug, PartialEq, Eq)] +#[repr(u8)] +pub enum AllocType { + Static(StaticAlloc), + Reserve(RsrvAlloc), +} + +impl AllocType { + pub fn new_static() -> Self { + Self::Static(StaticAlloc) + } + + pub fn new_rsrv() -> Self { + Self::Reserve(RsrvAlloc) + } +} +// Chunk manages memory range. +// The Chunk structure is filled into the layout before the base pointer. +#[derive(Debug)] +struct Chunk { + base: usize, + size: usize, + used: usize, + link: Link, // singly intrusive linkedlist +} + +impl Chunk { + fn new(base: usize, size: usize) -> Self { + Self { + base, + size, + used: 0, + link: Link::new(), + } + } +} + +intrusive_adapter!(ChunkAda = UnsafeRef<Chunk>: Chunk { link: Link }); + +const NUM_EXACT_LIST: usize = 0x100; +const HEADER_SIZE: usize = size_of::<usize>(); +const EXACT_MATCH_INCREMENT: usize = 0x8; +const MIN_BLOCK_SIZE: usize = 0x10; +const MAX_EXACT_SIZE: usize = MIN_BLOCK_SIZE + EXACT_MATCH_INCREMENT * (NUM_EXACT_LIST - 1); + +// Free block for allocating memory with exact size +#[repr(C)] +#[derive(Debug)] +struct BlockFree { + size: usize, + link: Link, // singly intrusive linkedlist +} + +// Used block for tracking allocated size and base pointer +#[repr(C)] +#[derive(Debug)] +struct BlockUsed { + size: usize, + payload: usize, +} + +impl BlockFree { + fn new(size: usize) -> Self { + Self { + size, + link: Link::new(), + } + } + + fn set_size(&mut self, size: usize) { + self.size = size; + } + + fn block_size(&self) -> usize { + self.size & SIZE_MASK + } +} + +impl BlockUsed { + fn new(size: usize) -> Self { + Self { size, payload: 0 } + } + + fn set_size(&mut self, size: usize) { + self.size = size; + } + + fn block_size(&self) -> usize { + self.size & SIZE_MASK + } + + fn is_alloced(&self) -> bool { + self.size & ALLOC_MASK == 0 + } + + fn set_alloced(&mut self) { + self.size |= ALLOC_MASK; + } + + fn clear_alloced(&mut self) { + self.size &= SIZE_MASK; + } +} + +intrusive_adapter!(BlockFreeAda = UnsafeRef<BlockFree>: BlockFree { link: Link }); + +/// Interior allocator for reserve memory management +/// +/// TODO: implement slab allocator mechanism +pub struct Reserve { + exact_blocks: [SinglyLinkedList<BlockFreeAda>; 256], + large_blocks: SinglyLinkedList<BlockFreeAda>, + chunks: SinglyLinkedList<ChunkAda>, + // The size of memory increment + incr_size: usize, + // statistics + allocated: usize, + total: usize, +} + +impl Reserve { + fn new(size: usize) -> Self { + let exact_blocks: [SinglyLinkedList<BlockFreeAda>; 256] = { + let mut exact_blocks: [MaybeUninit<SinglyLinkedList<BlockFreeAda>>; 256] = + MaybeUninit::uninit_array(); + for block in &mut exact_blocks { + block.write(SinglyLinkedList::new(BlockFreeAda::new())); + } + unsafe { transmute(exact_blocks) } Review Comment: Done, nice suggestion! -- This is an automated message from the Apache Git Service. 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