1 //! 这个文件内放置初始内核线程的代码。 2 3 use core::sync::atomic::{compiler_fence, Ordering}; 4 5 use alloc::{ffi::CString, string::ToString}; 6 use log::{debug, error}; 7 use system_error::SystemError; 8 9 use crate::{ 10 arch::{interrupt::TrapFrame, process::arch_switch_to_user}, 11 driver::{net::e1000e::e1000e::e1000e_init, virtio::virtio::virtio_probe}, 12 filesystem::vfs::core::mount_root_fs, 13 net::net_core::net_init, 14 process::{kthread::KernelThreadMechanism, stdio::stdio_init, ProcessFlags, ProcessManager}, 15 smp::smp_init, 16 syscall::Syscall, 17 }; 18 19 use super::initcall::do_initcalls; 20 21 pub fn initial_kernel_thread() -> i32 { 22 kernel_init().unwrap_or_else(|err| { 23 log::error!("Failed to initialize kernel: {:?}", err); 24 panic!() 25 }); 26 27 switch_to_user(); 28 } 29 30 fn kernel_init() -> Result<(), SystemError> { 31 KernelThreadMechanism::init_stage2(); 32 kenrel_init_freeable()?; 33 #[cfg(target_arch = "x86_64")] 34 crate::driver::disk::ahci::ahci_init() 35 .inspect_err(|e| log::error!("ahci_init failed: {:?}", e)) 36 .ok(); 37 virtio_probe(); 38 mount_root_fs().expect("Failed to mount root fs"); 39 e1000e_init(); 40 net_init().unwrap_or_else(|err| { 41 error!("Failed to initialize network: {:?}", err); 42 }); 43 44 debug!("initial kernel thread done."); 45 46 return Ok(()); 47 } 48 49 #[inline(never)] 50 fn kenrel_init_freeable() -> Result<(), SystemError> { 51 do_initcalls().unwrap_or_else(|err| { 52 panic!("Failed to initialize subsystems: {:?}", err); 53 }); 54 stdio_init().expect("Failed to initialize stdio"); 55 smp_init(); 56 57 return Ok(()); 58 } 59 60 /// 切换到用户态 61 #[inline(never)] 62 fn switch_to_user() -> ! { 63 let current_pcb = ProcessManager::current_pcb(); 64 65 // 删除kthread的标志 66 current_pcb.flags().remove(ProcessFlags::KTHREAD); 67 current_pcb.worker_private().take(); 68 69 *current_pcb.sched_info().sched_policy.write_irqsave() = crate::sched::SchedPolicy::CFS; 70 drop(current_pcb); 71 72 let mut trap_frame = TrapFrame::new(); 73 // 逐个尝试运行init进程 74 if try_to_run_init_process("/bin/dragonreach", &mut trap_frame).is_err() 75 && try_to_run_init_process("/bin/init", &mut trap_frame).is_err() 76 && try_to_run_init_process("/bin/sh", &mut trap_frame).is_err() 77 { 78 panic!("Failed to run init process: No working init found."); 79 } 80 81 // 需要确保执行到这里之后，上面所有的资源都已经释放（比如arc之类的） 82 compiler_fence(Ordering::SeqCst); 83 84 unsafe { arch_switch_to_user(trap_frame) }; 85 } 86 87 fn try_to_run_init_process(path: &str, trap_frame: &mut TrapFrame) -> Result<(), SystemError> { 88 if let Err(e) = run_init_process(path, trap_frame) { 89 if e != SystemError::ENOENT { 90 error!( 91 "Failed to run init process: {path} exists but couldn't execute it (error {:?})", 92 e 93 ); 94 } 95 return Err(e); 96 } 97 Ok(()) 98 } 99 100 fn run_init_process(path: &str, trap_frame: &mut TrapFrame) -> Result<(), SystemError> { 101 let argv = vec![CString::new(path).unwrap()]; 102 let envp = vec![CString::new("PATH=/").unwrap()]; 103 104 compiler_fence(Ordering::SeqCst); 105 Syscall::do_execve(path.to_string(), argv, envp, trap_frame)?; 106 Ok(()) 107 } 108