use core::sync::atomic::{compiler_fence, AtomicBool, Ordering}; use system_error::SystemError; use crate::{ arch::{ mm::{ kernel_page_flags, INNER_ALLOCATOR, KERNEL_BEGIN_PA, KERNEL_BEGIN_VA, KERNEL_END_PA, KERNEL_END_VA, }, MMArch, }, driver::firmware::efi::efi_manager, kdebug, kinfo, libs::lib_ui::screen_manager::scm_disable_put_to_window, mm::{ allocator::{buddy::BuddyAllocator, bump::BumpAllocator, page_frame::FrameAllocator}, kernel_mapper::KernelMapper, memblock::mem_block_manager, page::PageEntry, MemoryManagementArch, PageTableKind, PhysAddr, VirtAddr, }, }; use super::RiscV64MMArch; pub(super) static mut INITIAL_PGTABLE_VALUE: PhysAddr = PhysAddr::new(0); #[inline(never)] pub fn mm_early_init() { unsafe { init_kernel_addr() }; } unsafe fn init_kernel_addr() { extern "C" { /// 内核起始label fn boot_text_start_pa(); /// 内核结束位置的label fn _end(); fn _start(); /// 内核start标签被加载到的物理地址 fn __initial_start_load_paddr(); } let initial_start_load_pa = *(__initial_start_load_paddr as usize as *const usize); let offset = _start as usize - boot_text_start_pa as usize; let start_pa = initial_start_load_pa - offset; let offset2 = _end as usize - boot_text_start_pa as usize; let end_pa = start_pa + offset2; KERNEL_BEGIN_PA = PhysAddr::new(start_pa); KERNEL_END_PA = PhysAddr::new(end_pa); KERNEL_BEGIN_VA = VirtAddr::new(boot_text_start_pa as usize); KERNEL_END_VA = VirtAddr::new(_end as usize); kdebug!( "init_kernel_addr: \n\tKERNEL_BEGIN_PA: {KERNEL_BEGIN_PA:?} \tKERNEL_END_PA: {KERNEL_END_PA:?} \tKERNEL_BEGIN_VA: {KERNEL_BEGIN_VA:?} \tKERNEL_END_VA: {KERNEL_END_VA:?} " ); } pub(super) unsafe fn riscv_mm_init() -> Result<(), SystemError> { mem_block_manager() .reserve_block(KERNEL_BEGIN_PA, KERNEL_END_PA - KERNEL_BEGIN_PA) .expect("Failed to reserve kernel memory"); // 开启S-mode User Memory Access,允许内核访问用户空间 riscv::register::sstatus::set_sum(); let mut bump_allocator = BumpAllocator::::new(0); let _old_page_table = MMArch::table(PageTableKind::Kernel); let new_page_table: PhysAddr; // 使用bump分配器,把所有的内存页都映射到页表 { // kdebug!("to create new page table"); // 用bump allocator创建新的页表 let mut mapper: crate::mm::page::PageMapper> = crate::mm::page::PageMapper::::create( PageTableKind::Kernel, &mut bump_allocator, ) .expect("Failed to create page mapper"); new_page_table = mapper.table().phys(); // kdebug!("PageMapper created"); // 取消最开始时候,在head.S中指定的映射(暂时不刷新TLB) { let table = mapper.table(); let empty_entry = PageEntry::::from_usize(0); for i in 0..MMArch::PAGE_ENTRY_NUM { table .set_entry(i, empty_entry) .expect("Failed to empty page table entry"); } } kdebug!("Successfully emptied page table"); let total_num = mem_block_manager().total_initial_memory_regions(); for i in 0..total_num { let area = mem_block_manager().get_initial_memory_region(i).unwrap(); // kdebug!("area: base={:?}, size={:#x}, end={:?}", area.base, area.size, area.base + area.size); for i in 0..((area.size + MMArch::PAGE_SIZE - 1) / MMArch::PAGE_SIZE) { let paddr = area.base.add(i * MMArch::PAGE_SIZE); let vaddr = unsafe { MMArch::phys_2_virt(paddr) }.unwrap(); let flags = kernel_page_flags::(vaddr).set_execute(true); let flusher = mapper .map_phys(vaddr, paddr, flags) .expect("Failed to map frame"); // 暂时不刷新TLB flusher.ignore(); } } // 添加低地址的映射(在smp完成初始化之前,需要使用低地址的映射.初始化之后需要取消这一段映射) LowAddressRemapping::remap_at_low_address(&mut mapper); } unsafe { INITIAL_PGTABLE_VALUE = new_page_table; } kdebug!( "After mapping all physical memory, DragonOS used: {} KB", bump_allocator.usage().used().bytes() / 1024 ); // 初始化buddy_allocator let buddy_allocator = unsafe { BuddyAllocator::::new(bump_allocator).unwrap() }; // 设置全局的页帧分配器 unsafe { set_inner_allocator(buddy_allocator) }; kinfo!("Successfully initialized buddy allocator"); // 关闭显示输出 scm_disable_put_to_window(); // make the new page table current { let mut binding = INNER_ALLOCATOR.lock(); let mut allocator_guard = binding.as_mut().unwrap(); kdebug!("To enable new page table."); compiler_fence(Ordering::SeqCst); let mapper = crate::mm::page::PageMapper::::new( PageTableKind::Kernel, new_page_table, &mut allocator_guard, ); compiler_fence(Ordering::SeqCst); mapper.make_current(); compiler_fence(Ordering::SeqCst); // kdebug!("New page table enabled"); } kdebug!("Successfully enabled new page table"); kinfo!("riscv mm init done"); return Ok(()); } unsafe fn set_inner_allocator(allocator: BuddyAllocator) { static FLAG: AtomicBool = AtomicBool::new(false); if FLAG .compare_exchange(false, true, Ordering::SeqCst, Ordering::SeqCst) .is_err() { panic!("Cannot set inner allocator twice!"); } *INNER_ALLOCATOR.lock() = Some(allocator); } /// 低地址重映射的管理器 /// /// 低地址重映射的管理器,在smp初始化完成之前,需要使用低地址的映射,因此需要在smp初始化完成之后,取消这一段映射 pub struct LowAddressRemapping; impl LowAddressRemapping { pub unsafe fn remap_at_low_address( mapper: &mut crate::mm::page::PageMapper>, ) { let info = efi_manager().kernel_load_info().unwrap(); let base = PhysAddr::new(info.paddr as usize); let size = info.size as usize; for i in 0..(size / MMArch::PAGE_SIZE) { let paddr = PhysAddr::new(base.data() + i * MMArch::PAGE_SIZE); let vaddr = VirtAddr::new(base.data() + i * MMArch::PAGE_SIZE); let flags = kernel_page_flags::(vaddr).set_execute(true); let flusher = mapper .map_phys(vaddr, paddr, flags) .expect("Failed to map frame"); // 暂时不刷新TLB flusher.ignore(); } } /// 取消低地址的映射 pub unsafe fn unmap_at_low_address(flush: bool) { let mut mapper = KernelMapper::lock(); assert!(mapper.as_mut().is_some()); let info = efi_manager().kernel_load_info().unwrap(); let base = PhysAddr::new(info.paddr as usize); let size = info.size as usize; for i in 0..(size / MMArch::PAGE_SIZE) { let vaddr = VirtAddr::new(base.data() + i * MMArch::PAGE_SIZE); let (_, _, flusher) = mapper .as_mut() .unwrap() .unmap_phys(vaddr, true) .expect("Failed to unmap frame"); if flush == false { flusher.ignore(); } } } }