1393f6915SLoGin use core::{intrinsics::unlikely, sync::atomic::Ordering}; 2393f6915SLoGin 31496ba7bSLoGin use alloc::{string::ToString, sync::Arc}; 491e9d4abSLoGin use system_error::SystemError; 5c8025a88Slogin 6c8025a88Slogin use crate::{ 7393f6915SLoGin arch::{interrupt::TrapFrame, ipc::signal::Signal}, 8971462beSGnoCiYeH filesystem::procfs::procfs_register_pid, 9971462beSGnoCiYeH ipc::signal::flush_signal_handlers, 10971462beSGnoCiYeH libs::rwlock::RwLock, 11971462beSGnoCiYeH mm::VirtAddr, 12971462beSGnoCiYeH process::ProcessFlags, 13*f0c87a89SGnoCiYeH sched::{sched_cgroup_fork, sched_fork}, 14*f0c87a89SGnoCiYeH smp::core::smp_get_processor_id, 1591e9d4abSLoGin syscall::user_access::UserBufferWriter, 16c8025a88Slogin }; 1766f67c6aSlogin 181496ba7bSLoGin use super::{ 191496ba7bSLoGin kthread::{KernelThreadPcbPrivate, WorkerPrivate}, 201496ba7bSLoGin KernelStack, Pid, ProcessControlBlock, ProcessManager, 211496ba7bSLoGin }; 221a2eaa40Slogin 231496ba7bSLoGin bitflags! { 241496ba7bSLoGin /// 进程克隆标志 25971462beSGnoCiYeH pub struct CloneFlags: u64 { 261496ba7bSLoGin /// 在进程间共享虚拟内存空间 27971462beSGnoCiYeH const CLONE_VM = 0x00000100; 28971462beSGnoCiYeH /// 在进程间共享文件系统信息 29971462beSGnoCiYeH const CLONE_FS = 0x00000200; 301496ba7bSLoGin /// 共享打开的文件 31971462beSGnoCiYeH const CLONE_FILES = 0x00000400; 32971462beSGnoCiYeH /// 克隆时,与父进程共享信号处理结构体 33971462beSGnoCiYeH const CLONE_SIGHAND = 0x00000800; 34971462beSGnoCiYeH /// 返回进程的文件描述符 35971462beSGnoCiYeH const CLONE_PIDFD = 0x00001000; 36971462beSGnoCiYeH /// 使克隆对象成为父进程的跟踪对象 37971462beSGnoCiYeH const CLONE_PTRACE = 0x00002000; 38971462beSGnoCiYeH /// 在执行 exec() 或 _exit() 之前挂起父进程的执行 39971462beSGnoCiYeH const CLONE_VFORK = 0x00004000; 40971462beSGnoCiYeH /// 使克隆对象的父进程为调用进程的父进程 41971462beSGnoCiYeH const CLONE_PARENT = 0x00008000; 42971462beSGnoCiYeH /// 拷贝线程 43971462beSGnoCiYeH const CLONE_THREAD = 0x00010000; 44971462beSGnoCiYeH /// 创建一个新的命名空间,其中包含独立的文件系统挂载点层次结构。 45971462beSGnoCiYeH const CLONE_NEWNS = 0x00020000; 46971462beSGnoCiYeH /// 与父进程共享 System V 信号量。 47971462beSGnoCiYeH const CLONE_SYSVSEM = 0x00040000; 48971462beSGnoCiYeH /// 设置其线程本地存储 49971462beSGnoCiYeH const CLONE_SETTLS = 0x00080000; 50971462beSGnoCiYeH /// 设置partent_tid地址为子进程线程 ID 51971462beSGnoCiYeH const CLONE_PARENT_SETTID = 0x00100000; 52971462beSGnoCiYeH /// 在子进程中设置一个清除线程 ID 的用户空间地址 53971462beSGnoCiYeH const CLONE_CHILD_CLEARTID = 0x00200000; 54971462beSGnoCiYeH /// 创建一个新线程,将其设置为分离状态 55971462beSGnoCiYeH const CLONE_DETACHED = 0x00400000; 56971462beSGnoCiYeH /// 使其在创建者进程或线程视角下成为无法跟踪的。 57971462beSGnoCiYeH const CLONE_UNTRACED = 0x00800000; 58971462beSGnoCiYeH /// 设置其子进程线程 ID 59971462beSGnoCiYeH const CLONE_CHILD_SETTID = 0x01000000; 60971462beSGnoCiYeH /// 将其放置在一个新的 cgroup 命名空间中 61971462beSGnoCiYeH const CLONE_NEWCGROUP = 0x02000000; 62971462beSGnoCiYeH /// 将其放置在一个新的 UTS 命名空间中 63971462beSGnoCiYeH const CLONE_NEWUTS = 0x04000000; 64971462beSGnoCiYeH /// 将其放置在一个新的 IPC 命名空间中 65971462beSGnoCiYeH const CLONE_NEWIPC = 0x08000000; 66971462beSGnoCiYeH /// 将其放置在一个新的用户命名空间中 67971462beSGnoCiYeH const CLONE_NEWUSER = 0x10000000; 68971462beSGnoCiYeH /// 将其放置在一个新的 PID 命名空间中 69971462beSGnoCiYeH const CLONE_NEWPID = 0x20000000; 70971462beSGnoCiYeH /// 将其放置在一个新的网络命名空间中 71971462beSGnoCiYeH const CLONE_NEWNET = 0x40000000; 72971462beSGnoCiYeH /// 在新的 I/O 上下文中运行它 73971462beSGnoCiYeH const CLONE_IO = 0x80000000; 74971462beSGnoCiYeH /// 克隆时,与父进程共享信号结构体 75971462beSGnoCiYeH const CLONE_SIGNAL = 0x00010000 | 0x00000800; 76971462beSGnoCiYeH /// 克隆时,将原本被设置为SIG_IGNORE的信号,设置回SIG_DEFAULT 77971462beSGnoCiYeH const CLONE_CLEAR_SIGHAND = 0x100000000; 78971462beSGnoCiYeH } 79971462beSGnoCiYeH } 80971462beSGnoCiYeH 81971462beSGnoCiYeH /// ## clone与clone3系统调用的参数载体 82971462beSGnoCiYeH /// 83971462beSGnoCiYeH /// 因为这两个系统调用的参数很多,所以有这样一个载体更灵活 84971462beSGnoCiYeH /// 85971462beSGnoCiYeH /// 仅仅作为参数传递 86971462beSGnoCiYeH #[derive(Debug, Clone, Copy)] 87971462beSGnoCiYeH pub struct KernelCloneArgs { 88971462beSGnoCiYeH pub flags: CloneFlags, 89971462beSGnoCiYeH 90971462beSGnoCiYeH // 下列属性均来自用户空间 91971462beSGnoCiYeH pub pidfd: VirtAddr, 92971462beSGnoCiYeH pub child_tid: VirtAddr, 93971462beSGnoCiYeH pub parent_tid: VirtAddr, 94971462beSGnoCiYeH pub set_tid: VirtAddr, 95971462beSGnoCiYeH 96393f6915SLoGin /// 进程退出时发送的信号 97393f6915SLoGin pub exit_signal: Signal, 98971462beSGnoCiYeH 99971462beSGnoCiYeH pub stack: usize, 100971462beSGnoCiYeH // clone3用到 101971462beSGnoCiYeH pub stack_size: usize, 102971462beSGnoCiYeH pub tls: usize, 103971462beSGnoCiYeH 104971462beSGnoCiYeH pub set_tid_size: usize, 105971462beSGnoCiYeH pub cgroup: i32, 106971462beSGnoCiYeH 107971462beSGnoCiYeH pub io_thread: bool, 108971462beSGnoCiYeH pub kthread: bool, 109971462beSGnoCiYeH pub idle: bool, 110971462beSGnoCiYeH pub func: VirtAddr, 111971462beSGnoCiYeH pub fn_arg: VirtAddr, 112971462beSGnoCiYeH // cgrp 和 cset? 113971462beSGnoCiYeH } 114971462beSGnoCiYeH 115971462beSGnoCiYeH impl KernelCloneArgs { 116971462beSGnoCiYeH pub fn new() -> Self { 117971462beSGnoCiYeH let null_addr = VirtAddr::new(0); 118971462beSGnoCiYeH Self { 119971462beSGnoCiYeH flags: unsafe { CloneFlags::from_bits_unchecked(0) }, 120971462beSGnoCiYeH pidfd: null_addr, 121971462beSGnoCiYeH child_tid: null_addr, 122971462beSGnoCiYeH parent_tid: null_addr, 123971462beSGnoCiYeH set_tid: null_addr, 124393f6915SLoGin exit_signal: Signal::SIGCHLD, 125971462beSGnoCiYeH stack: 0, 126971462beSGnoCiYeH stack_size: 0, 127971462beSGnoCiYeH tls: 0, 128971462beSGnoCiYeH set_tid_size: 0, 129971462beSGnoCiYeH cgroup: 0, 130971462beSGnoCiYeH io_thread: false, 131971462beSGnoCiYeH kthread: false, 132971462beSGnoCiYeH idle: false, 133971462beSGnoCiYeH func: null_addr, 134971462beSGnoCiYeH fn_arg: null_addr, 135971462beSGnoCiYeH } 136c8025a88Slogin } 13766f67c6aSlogin } 13866f67c6aSlogin 1391496ba7bSLoGin impl ProcessManager { 1401496ba7bSLoGin /// 创建一个新进程 1411496ba7bSLoGin /// 1421496ba7bSLoGin /// ## 参数 1431496ba7bSLoGin /// 1441496ba7bSLoGin /// - `current_trapframe`: 当前进程的trapframe 1451496ba7bSLoGin /// - `clone_flags`: 进程克隆标志 1461496ba7bSLoGin /// 1471496ba7bSLoGin /// ## 返回值 1481496ba7bSLoGin /// 1491496ba7bSLoGin /// - 成功:返回新进程的pid 1501496ba7bSLoGin /// - 失败:返回Err(SystemError),fork失败的话,子线程不会执行。 1511496ba7bSLoGin /// 1521496ba7bSLoGin /// ## Safety 1531496ba7bSLoGin /// 1541496ba7bSLoGin /// - fork失败的话,子线程不会执行。 1551496ba7bSLoGin pub fn fork( 156840045afSLoGin current_trapframe: &TrapFrame, 1571496ba7bSLoGin clone_flags: CloneFlags, 1581496ba7bSLoGin ) -> Result<Pid, SystemError> { 1591496ba7bSLoGin let current_pcb = ProcessManager::current_pcb(); 1604fda81ceSLoGin 1614fda81ceSLoGin let new_kstack: KernelStack = KernelStack::new()?; 1624fda81ceSLoGin 1631496ba7bSLoGin let name = current_pcb.basic().name().to_string(); 1640d6cf65aSLoGin 1651496ba7bSLoGin let pcb = ProcessControlBlock::new(name, new_kstack); 1661496ba7bSLoGin 167971462beSGnoCiYeH let mut args = KernelCloneArgs::new(); 168971462beSGnoCiYeH args.flags = clone_flags; 169393f6915SLoGin args.exit_signal = Signal::SIGCHLD; 17059fdb447SLoGin Self::copy_process(¤t_pcb, &pcb, args, current_trapframe).map_err(|e| { 17159fdb447SLoGin kerror!( 17259fdb447SLoGin "fork: Failed to copy process, current pid: [{:?}], new pid: [{:?}]. Error: {:?}", 17359fdb447SLoGin current_pcb.pid(), 17459fdb447SLoGin pcb.pid(), 17559fdb447SLoGin e 17659fdb447SLoGin ); 17759fdb447SLoGin e 17859fdb447SLoGin })?; 1791496ba7bSLoGin ProcessManager::add_pcb(pcb.clone()); 1801496ba7bSLoGin 1811496ba7bSLoGin // 向procfs注册进程 1821496ba7bSLoGin procfs_register_pid(pcb.pid()).unwrap_or_else(|e| { 1831496ba7bSLoGin panic!( 1841496ba7bSLoGin "fork: Failed to register pid to procfs, pid: [{:?}]. Error: {:?}", 1851496ba7bSLoGin pcb.pid(), 1861496ba7bSLoGin e 1871496ba7bSLoGin ) 1881496ba7bSLoGin }); 1891496ba7bSLoGin 190*f0c87a89SGnoCiYeH pcb.sched_info().set_on_cpu(Some(smp_get_processor_id())); 191*f0c87a89SGnoCiYeH 1921496ba7bSLoGin ProcessManager::wakeup(&pcb).unwrap_or_else(|e| { 1931496ba7bSLoGin panic!( 1941496ba7bSLoGin "fork: Failed to wakeup new process, pid: [{:?}]. Error: {:?}", 1951496ba7bSLoGin pcb.pid(), 1961496ba7bSLoGin e 1971496ba7bSLoGin ) 1981496ba7bSLoGin }); 1991496ba7bSLoGin 2001496ba7bSLoGin return Ok(pcb.pid()); 2011496ba7bSLoGin } 2021496ba7bSLoGin 2031496ba7bSLoGin fn copy_flags( 2041496ba7bSLoGin clone_flags: &CloneFlags, 2051496ba7bSLoGin new_pcb: &Arc<ProcessControlBlock>, 2061496ba7bSLoGin ) -> Result<(), SystemError> { 2071496ba7bSLoGin if clone_flags.contains(CloneFlags::CLONE_VM) { 2081496ba7bSLoGin new_pcb.flags().insert(ProcessFlags::VFORK); 2091496ba7bSLoGin } 210b5b571e0SLoGin *new_pcb.flags.get_mut() = *ProcessManager::current_pcb().flags(); 2111496ba7bSLoGin return Ok(()); 21266f67c6aSlogin } 21340fe15e0SLoGin 21440fe15e0SLoGin /// 拷贝进程的地址空间 21540fe15e0SLoGin /// 21640fe15e0SLoGin /// ## 参数 21740fe15e0SLoGin /// 21840fe15e0SLoGin /// - `clone_vm`: 是否与父进程共享地址空间。true表示共享 21940fe15e0SLoGin /// - `new_pcb`: 新进程的pcb 22040fe15e0SLoGin /// 22140fe15e0SLoGin /// ## 返回值 22240fe15e0SLoGin /// 22340fe15e0SLoGin /// - 成功:返回Ok(()) 22440fe15e0SLoGin /// - 失败:返回Err(SystemError) 22540fe15e0SLoGin /// 22640fe15e0SLoGin /// ## Panic 22740fe15e0SLoGin /// 22840fe15e0SLoGin /// - 如果当前进程没有用户地址空间,则panic 2294fda81ceSLoGin #[inline(never)] 2301496ba7bSLoGin fn copy_mm( 2311496ba7bSLoGin clone_flags: &CloneFlags, 2321496ba7bSLoGin current_pcb: &Arc<ProcessControlBlock>, 2331496ba7bSLoGin new_pcb: &Arc<ProcessControlBlock>, 2341496ba7bSLoGin ) -> Result<(), SystemError> { 2351496ba7bSLoGin let old_address_space = current_pcb.basic().user_vm().unwrap_or_else(|| { 2361496ba7bSLoGin panic!( 2371496ba7bSLoGin "copy_mm: Failed to get address space of current process, current pid: [{:?}]", 2381496ba7bSLoGin current_pcb.pid() 2391496ba7bSLoGin ) 2401496ba7bSLoGin }); 24140fe15e0SLoGin 2421496ba7bSLoGin if clone_flags.contains(CloneFlags::CLONE_VM) { 2431496ba7bSLoGin unsafe { new_pcb.basic_mut().set_user_vm(Some(old_address_space)) }; 24440fe15e0SLoGin return Ok(()); 24540fe15e0SLoGin } 2460d6cf65aSLoGin let new_address_space = old_address_space.write_irqsave().try_clone().unwrap_or_else(|e| { 24740fe15e0SLoGin panic!( 2481496ba7bSLoGin "copy_mm: Failed to clone address space of current process, current pid: [{:?}], new pid: [{:?}]. Error: {:?}", 2491496ba7bSLoGin current_pcb.pid(), new_pcb.pid(), e 25040fe15e0SLoGin ) 25140fe15e0SLoGin }); 2521496ba7bSLoGin unsafe { new_pcb.basic_mut().set_user_vm(Some(new_address_space)) }; 25340fe15e0SLoGin return Ok(()); 25440fe15e0SLoGin } 2551496ba7bSLoGin 2560d6cf65aSLoGin #[inline(never)] 2571496ba7bSLoGin fn copy_files( 2581496ba7bSLoGin clone_flags: &CloneFlags, 2591496ba7bSLoGin current_pcb: &Arc<ProcessControlBlock>, 2601496ba7bSLoGin new_pcb: &Arc<ProcessControlBlock>, 2611496ba7bSLoGin ) -> Result<(), SystemError> { 2621496ba7bSLoGin // 如果不共享文件描述符表,则拷贝文件描述符表 2631496ba7bSLoGin if !clone_flags.contains(CloneFlags::CLONE_FILES) { 2641496ba7bSLoGin let new_fd_table = current_pcb.basic().fd_table().unwrap().read().clone(); 2651496ba7bSLoGin let new_fd_table = Arc::new(RwLock::new(new_fd_table)); 2661496ba7bSLoGin new_pcb.basic_mut().set_fd_table(Some(new_fd_table)); 267bb0e4d41SGnoCiYeH } else { 2681496ba7bSLoGin // 如果共享文件描述符表,则直接拷贝指针 2691496ba7bSLoGin new_pcb 2701496ba7bSLoGin .basic_mut() 2711496ba7bSLoGin .set_fd_table(current_pcb.basic().fd_table().clone()); 272bb0e4d41SGnoCiYeH } 2731496ba7bSLoGin 2741496ba7bSLoGin return Ok(()); 2751496ba7bSLoGin } 2761496ba7bSLoGin 2771496ba7bSLoGin #[allow(dead_code)] 2781496ba7bSLoGin fn copy_sighand( 2793c82aa56SChiichen clone_flags: &CloneFlags, 2803c82aa56SChiichen current_pcb: &Arc<ProcessControlBlock>, 2813c82aa56SChiichen new_pcb: &Arc<ProcessControlBlock>, 2821496ba7bSLoGin ) -> Result<(), SystemError> { 2833c82aa56SChiichen // // 将信号的处理函数设置为default(除了那些被手动屏蔽的) 2843c82aa56SChiichen if clone_flags.contains(CloneFlags::CLONE_CLEAR_SIGHAND) { 2853c82aa56SChiichen flush_signal_handlers(new_pcb.clone(), false); 2863c82aa56SChiichen } 2873c82aa56SChiichen 2883c82aa56SChiichen if clone_flags.contains(CloneFlags::CLONE_SIGHAND) { 289b5b571e0SLoGin new_pcb.sig_struct_irqsave().handlers = current_pcb.sig_struct_irqsave().handlers; 2903c82aa56SChiichen } 2911496ba7bSLoGin return Ok(()); 2921496ba7bSLoGin } 293971462beSGnoCiYeH 294971462beSGnoCiYeH /// 拷贝进程信息 295971462beSGnoCiYeH /// 296971462beSGnoCiYeH /// ## panic: 297971462beSGnoCiYeH /// 某一步拷贝失败时会引发panic 298971462beSGnoCiYeH /// 例如:copy_mm等失败时会触发panic 299971462beSGnoCiYeH /// 300971462beSGnoCiYeH /// ## 参数 301971462beSGnoCiYeH /// 302971462beSGnoCiYeH /// - clone_flags 标志位 3030d6cf65aSLoGin /// - current_pcb 拷贝源pcb 3040d6cf65aSLoGin /// - pcb 目标pcb 305971462beSGnoCiYeH /// 306971462beSGnoCiYeH /// ## return 307971462beSGnoCiYeH /// - 发生错误时返回Err(SystemError) 3084fda81ceSLoGin #[inline(never)] 309971462beSGnoCiYeH pub fn copy_process( 310971462beSGnoCiYeH current_pcb: &Arc<ProcessControlBlock>, 311971462beSGnoCiYeH pcb: &Arc<ProcessControlBlock>, 312971462beSGnoCiYeH clone_args: KernelCloneArgs, 313840045afSLoGin current_trapframe: &TrapFrame, 314971462beSGnoCiYeH ) -> Result<(), SystemError> { 315971462beSGnoCiYeH let clone_flags = clone_args.flags; 316971462beSGnoCiYeH // 不允许与不同namespace的进程共享根目录 317971462beSGnoCiYeH if (clone_flags == (CloneFlags::CLONE_NEWNS | CloneFlags::CLONE_FS)) 318971462beSGnoCiYeH || clone_flags == (CloneFlags::CLONE_NEWUSER | CloneFlags::CLONE_FS) 319971462beSGnoCiYeH { 320971462beSGnoCiYeH return Err(SystemError::EINVAL); 321971462beSGnoCiYeH } 322971462beSGnoCiYeH 323971462beSGnoCiYeH // 线程组必须共享信号,分离线程只能在线程组内启动。 324971462beSGnoCiYeH if clone_flags.contains(CloneFlags::CLONE_THREAD) 325971462beSGnoCiYeH && !clone_flags.contains(CloneFlags::CLONE_SIGHAND) 326971462beSGnoCiYeH { 327971462beSGnoCiYeH return Err(SystemError::EINVAL); 328971462beSGnoCiYeH } 329971462beSGnoCiYeH 330971462beSGnoCiYeH // 共享信号处理器意味着共享vm。 331971462beSGnoCiYeH // 线程组也意味着共享vm。阻止这种情况可以简化其他代码。 332971462beSGnoCiYeH if clone_flags.contains(CloneFlags::CLONE_SIGHAND) 333971462beSGnoCiYeH && !clone_flags.contains(CloneFlags::CLONE_VM) 334971462beSGnoCiYeH { 335971462beSGnoCiYeH return Err(SystemError::EINVAL); 336971462beSGnoCiYeH } 337971462beSGnoCiYeH 338971462beSGnoCiYeH // TODO: 处理CLONE_PARENT 与 SIGNAL_UNKILLABLE的情况 339971462beSGnoCiYeH 340971462beSGnoCiYeH // 如果新进程使用不同的 pid 或 namespace, 341971462beSGnoCiYeH // 则不允许它与分叉任务共享线程组。 342b5b571e0SLoGin if clone_flags.contains(CloneFlags::CLONE_THREAD) 343b5b571e0SLoGin && clone_flags.contains(CloneFlags::CLONE_NEWUSER | CloneFlags::CLONE_NEWPID) 344b5b571e0SLoGin { 345971462beSGnoCiYeH return Err(SystemError::EINVAL); 346971462beSGnoCiYeH // TODO: 判断新进程与当前进程namespace是否相同,不同则返回错误 347971462beSGnoCiYeH } 348971462beSGnoCiYeH 349971462beSGnoCiYeH // 如果新进程将处于不同的time namespace, 350971462beSGnoCiYeH // 则不能让它共享vm或线程组。 351971462beSGnoCiYeH if clone_flags.contains(CloneFlags::CLONE_THREAD | CloneFlags::CLONE_VM) { 352971462beSGnoCiYeH // TODO: 判断time namespace,不同则返回错误 353971462beSGnoCiYeH } 354971462beSGnoCiYeH 355971462beSGnoCiYeH if clone_flags.contains(CloneFlags::CLONE_PIDFD) 356971462beSGnoCiYeH && clone_flags.contains(CloneFlags::CLONE_DETACHED | CloneFlags::CLONE_THREAD) 357971462beSGnoCiYeH { 358971462beSGnoCiYeH return Err(SystemError::EINVAL); 359971462beSGnoCiYeH } 360971462beSGnoCiYeH 361971462beSGnoCiYeH // TODO: 克隆前应该锁信号处理,等待克隆完成后再处理 362971462beSGnoCiYeH 363971462beSGnoCiYeH // 克隆架构相关 36416033951SGnoCiYeH let guard = current_pcb.arch_info_irqsave(); 3650d6cf65aSLoGin unsafe { pcb.arch_info().clone_from(&guard) }; 36616033951SGnoCiYeH drop(guard); 367971462beSGnoCiYeH 368971462beSGnoCiYeH // 为内核线程设置WorkerPrivate 369971462beSGnoCiYeH if current_pcb.flags().contains(ProcessFlags::KTHREAD) { 370971462beSGnoCiYeH *pcb.worker_private() = 371971462beSGnoCiYeH Some(WorkerPrivate::KernelThread(KernelThreadPcbPrivate::new())); 372971462beSGnoCiYeH } 373971462beSGnoCiYeH 374971462beSGnoCiYeH // 设置clear_child_tid,在线程结束时将其置0以通知父进程 375971462beSGnoCiYeH if clone_flags.contains(CloneFlags::CLONE_CHILD_CLEARTID) { 37652bcb59eSGnoCiYeH pcb.thread.write_irqsave().clear_child_tid = Some(clone_args.child_tid); 377971462beSGnoCiYeH } 378971462beSGnoCiYeH 379971462beSGnoCiYeH // 设置child_tid,意味着子线程能够知道自己的id 380971462beSGnoCiYeH if clone_flags.contains(CloneFlags::CLONE_CHILD_SETTID) { 38152bcb59eSGnoCiYeH pcb.thread.write_irqsave().set_child_tid = Some(clone_args.child_tid); 382971462beSGnoCiYeH } 383971462beSGnoCiYeH 384971462beSGnoCiYeH // 将子进程/线程的id存储在用户态传进的地址中 385971462beSGnoCiYeH if clone_flags.contains(CloneFlags::CLONE_PARENT_SETTID) { 386971462beSGnoCiYeH let mut writer = UserBufferWriter::new( 387971462beSGnoCiYeH clone_args.parent_tid.data() as *mut i32, 388971462beSGnoCiYeH core::mem::size_of::<i32>(), 389971462beSGnoCiYeH true, 390971462beSGnoCiYeH )?; 391971462beSGnoCiYeH 392971462beSGnoCiYeH writer.copy_one_to_user(&(pcb.pid().0 as i32), 0)?; 393971462beSGnoCiYeH } 394971462beSGnoCiYeH 395*f0c87a89SGnoCiYeH sched_fork(pcb).unwrap_or_else(|e| { 396*f0c87a89SGnoCiYeH panic!( 397*f0c87a89SGnoCiYeH "fork: Failed to set sched info from current process, current pid: [{:?}], new pid: [{:?}]. Error: {:?}", 398*f0c87a89SGnoCiYeH current_pcb.pid(), pcb.pid(), e 399*f0c87a89SGnoCiYeH ) 400*f0c87a89SGnoCiYeH }); 401*f0c87a89SGnoCiYeH 402971462beSGnoCiYeH // 拷贝标志位 403b5b571e0SLoGin Self::copy_flags(&clone_flags, pcb).unwrap_or_else(|e| { 404971462beSGnoCiYeH panic!( 405971462beSGnoCiYeH "fork: Failed to copy flags from current process, current pid: [{:?}], new pid: [{:?}]. Error: {:?}", 406971462beSGnoCiYeH current_pcb.pid(), pcb.pid(), e 407971462beSGnoCiYeH ) 408971462beSGnoCiYeH }); 409971462beSGnoCiYeH 410971462beSGnoCiYeH // 拷贝用户地址空间 411b5b571e0SLoGin Self::copy_mm(&clone_flags, current_pcb, pcb).unwrap_or_else(|e| { 412971462beSGnoCiYeH panic!( 413971462beSGnoCiYeH "fork: Failed to copy mm from current process, current pid: [{:?}], new pid: [{:?}]. Error: {:?}", 414971462beSGnoCiYeH current_pcb.pid(), pcb.pid(), e 415971462beSGnoCiYeH ) 416971462beSGnoCiYeH }); 417971462beSGnoCiYeH 418971462beSGnoCiYeH // 拷贝文件描述符表 419b5b571e0SLoGin Self::copy_files(&clone_flags, current_pcb, pcb).unwrap_or_else(|e| { 420971462beSGnoCiYeH panic!( 421971462beSGnoCiYeH "fork: Failed to copy files from current process, current pid: [{:?}], new pid: [{:?}]. Error: {:?}", 422971462beSGnoCiYeH current_pcb.pid(), pcb.pid(), e 423971462beSGnoCiYeH ) 424971462beSGnoCiYeH }); 425971462beSGnoCiYeH 426393f6915SLoGin // 拷贝信号相关数据 427b5b571e0SLoGin Self::copy_sighand(&clone_flags, current_pcb, pcb).unwrap_or_else(|e| { 428393f6915SLoGin panic!( 429393f6915SLoGin "fork: Failed to copy sighand from current process, current pid: [{:?}], new pid: [{:?}]. Error: {:?}", 430393f6915SLoGin current_pcb.pid(), pcb.pid(), e 431393f6915SLoGin ) 432b5b571e0SLoGin }); 433971462beSGnoCiYeH 434971462beSGnoCiYeH // 拷贝线程 435b5b571e0SLoGin Self::copy_thread(current_pcb, pcb, clone_args,current_trapframe).unwrap_or_else(|e| { 436971462beSGnoCiYeH panic!( 437971462beSGnoCiYeH "fork: Failed to copy thread from current process, current pid: [{:?}], new pid: [{:?}]. Error: {:?}", 438971462beSGnoCiYeH current_pcb.pid(), pcb.pid(), e 439971462beSGnoCiYeH ) 440971462beSGnoCiYeH }); 441971462beSGnoCiYeH 442393f6915SLoGin // 设置线程组id、组长 443393f6915SLoGin if clone_flags.contains(CloneFlags::CLONE_THREAD) { 44452bcb59eSGnoCiYeH pcb.thread.write_irqsave().group_leader = 44552bcb59eSGnoCiYeH current_pcb.thread.read_irqsave().group_leader.clone(); 446393f6915SLoGin unsafe { 447393f6915SLoGin let ptr = pcb.as_ref() as *const ProcessControlBlock as *mut ProcessControlBlock; 448393f6915SLoGin (*ptr).tgid = current_pcb.tgid; 449393f6915SLoGin } 450393f6915SLoGin } else { 451b5b571e0SLoGin pcb.thread.write_irqsave().group_leader = Arc::downgrade(pcb); 452393f6915SLoGin unsafe { 453393f6915SLoGin let ptr = pcb.as_ref() as *const ProcessControlBlock as *mut ProcessControlBlock; 454393f6915SLoGin (*ptr).tgid = pcb.tgid; 455393f6915SLoGin } 456393f6915SLoGin } 457393f6915SLoGin 458393f6915SLoGin // CLONE_PARENT re-uses the old parent 459393f6915SLoGin if clone_flags.contains(CloneFlags::CLONE_PARENT | CloneFlags::CLONE_THREAD) { 46052bcb59eSGnoCiYeH *pcb.real_parent_pcb.write_irqsave() = 46152bcb59eSGnoCiYeH current_pcb.real_parent_pcb.read_irqsave().clone(); 462393f6915SLoGin 463393f6915SLoGin if clone_flags.contains(CloneFlags::CLONE_THREAD) { 464393f6915SLoGin pcb.exit_signal.store(Signal::INVALID, Ordering::SeqCst); 465393f6915SLoGin } else { 46652bcb59eSGnoCiYeH let leader = current_pcb.thread.read_irqsave().group_leader(); 467393f6915SLoGin if unlikely(leader.is_none()) { 468393f6915SLoGin panic!( 469393f6915SLoGin "fork: Failed to get leader of current process, current pid: [{:?}]", 470393f6915SLoGin current_pcb.pid() 471393f6915SLoGin ); 472393f6915SLoGin } 473393f6915SLoGin 474393f6915SLoGin pcb.exit_signal.store( 475393f6915SLoGin leader.unwrap().exit_signal.load(Ordering::SeqCst), 476393f6915SLoGin Ordering::SeqCst, 477393f6915SLoGin ); 478393f6915SLoGin } 479393f6915SLoGin } else { 480393f6915SLoGin // 新创建的进程,设置其父进程为当前进程 481b5b571e0SLoGin *pcb.real_parent_pcb.write_irqsave() = Arc::downgrade(current_pcb); 482393f6915SLoGin pcb.exit_signal 483393f6915SLoGin .store(clone_args.exit_signal, Ordering::SeqCst); 484393f6915SLoGin } 485393f6915SLoGin 486e7071df6SLoGin // todo: 增加线程组相关的逻辑。 参考 https://code.dragonos.org.cn/xref/linux-6.1.9/kernel/fork.c#2437 487393f6915SLoGin 488*f0c87a89SGnoCiYeH sched_cgroup_fork(pcb); 489*f0c87a89SGnoCiYeH 490971462beSGnoCiYeH Ok(()) 491971462beSGnoCiYeH } 4921496ba7bSLoGin } 493