1 use core::{arch::asm, mem::ManuallyDrop}; 2 3 use alloc::{ 4 string::String, 5 sync::{Arc, Weak}, 6 vec::Vec, 7 }; 8 use system_error::SystemError; 9 10 use crate::{ 11 kerror, 12 mm::VirtAddr, 13 process::{fork::KernelCloneArgs, KernelStack, ProcessControlBlock, ProcessManager}, 14 }; 15 16 use super::interrupt::TrapFrame; 17 18 pub mod idle; 19 pub mod kthread; 20 pub mod syscall; 21 22 #[allow(dead_code)] 23 #[repr(align(32768))] 24 union InitProcUnion { 25 /// 用于存放idle进程的内核栈 26 idle_stack: [u8; 32768], 27 } 28 29 #[link_section = ".data.init_proc_union"] 30 #[no_mangle] 31 static BSP_IDLE_STACK_SPACE: InitProcUnion = InitProcUnion { 32 idle_stack: [0; 32768], 33 }; 34 35 pub unsafe fn arch_switch_to_user(path: String, argv: Vec<String>, envp: Vec<String>) -> ! { 36 unimplemented!("RiscV64 arch_switch_to_user") 37 } 38 39 impl ProcessManager { 40 pub fn arch_init() { 41 // do nothing 42 } 43 44 /// fork的过程中复制线程 45 /// 46 /// 由于这个过程与具体的架构相关，所以放在这里 47 pub fn copy_thread( 48 current_pcb: &Arc<ProcessControlBlock>, 49 new_pcb: &Arc<ProcessControlBlock>, 50 clone_args: KernelCloneArgs, 51 current_trapframe: &TrapFrame, 52 ) -> Result<(), SystemError> { 53 unimplemented!("ProcessManager::copy_thread") 54 } 55 56 /// 切换进程 57 /// 58 /// ## 参数 59 /// 60 /// - `prev`：上一个进程的pcb 61 /// - `next`：下一个进程的pcb 62 pub unsafe fn switch_process(prev: Arc<ProcessControlBlock>, next: Arc<ProcessControlBlock>) { 63 // todo: https://code.dragonos.org.cn/xref/linux-6.6.21/arch/riscv/include/asm/switch_to.h#76 64 unimplemented!("ProcessManager::switch_process") 65 } 66 } 67 68 impl ProcessControlBlock { 69 /// 获取当前进程的pcb 70 pub fn arch_current_pcb() -> Arc<Self> { 71 // 获取栈指针 72 let mut sp: usize; 73 unsafe { asm!("mv {}, sp", lateout(reg) sp, options(nostack)) }; 74 let ptr = VirtAddr::new(sp); 75 76 let stack_base = VirtAddr::new(ptr.data() & (!(KernelStack::ALIGN - 1))); 77 78 // 从内核栈的最低地址处取出pcb的地址 79 let p = stack_base.data() as *const *const ProcessControlBlock; 80 if core::intrinsics::unlikely((unsafe { *p }).is_null()) { 81 kerror!("p={:p}", p); 82 panic!("current_pcb is null"); 83 } 84 unsafe { 85 // 为了防止内核栈的pcb weak 指针被释放，这里需要将其包装一下 86 let weak_wrapper: ManuallyDrop<Weak<ProcessControlBlock>> = 87 ManuallyDrop::new(Weak::from_raw(*p)); 88 89 let new_arc: Arc<ProcessControlBlock> = weak_wrapper.upgrade().unwrap(); 90 return new_arc; 91 } 92 } 93 } 94 95 /// PCB中与架构相关的信息 96 #[derive(Debug)] 97 #[allow(dead_code)] 98 pub struct ArchPCBInfo { 99 // todo: add arch related fields 100 } 101 102 #[allow(dead_code)] 103 impl ArchPCBInfo { 104 /// 创建一个新的ArchPCBInfo 105 /// 106 /// ## 参数 107 /// 108 /// - `kstack`：内核栈的引用 109 /// 110 /// ## 返回值 111 /// 112 /// 返回一个新的ArchPCBInfo 113 pub fn new(kstack: &KernelStack) -> Self { 114 Self {} 115 } 116 // ### 从另一个ArchPCBInfo处clone,但是保留部分字段不变 117 pub fn clone_from(&mut self, from: &Self) { 118 unimplemented!("ArchPCBInfo::clone_from") 119 } 120 } 121