1 use alloc::{string::String, sync::Arc, vec::Vec}; 2 3 use crate::{ 4 arch::{ 5 interrupt::TrapFrame, 6 process::table::{USER_CS, USER_DS}, 7 CurrentIrqArch, 8 }, 9 exception::InterruptArch, 10 mm::ucontext::AddressSpace, 11 process::{ 12 exec::{load_binary_file, ExecParam, ExecParamFlags}, 13 ProcessControlBlock, ProcessManager, 14 }, 15 syscall::{user_access::UserBufferWriter, Syscall, SystemError}, 16 }; 17 18 impl Syscall { 19 pub fn do_execve( 20 path: String, 21 argv: Vec<String>, 22 envp: Vec<String>, 23 regs: &mut TrapFrame, 24 ) -> Result<(), SystemError> { 25 // kdebug!( 26 // "tmp_rs_execve: path: {:?}, argv: {:?}, envp: {:?}\n", 27 // path, 28 // argv, 29 // envp 30 // ); 31 // 关中断，防止在设置地址空间的时候，发生中断，然后进调度器，出现错误。 32 let irq_guard = unsafe { CurrentIrqArch::save_and_disable_irq() }; 33 let pcb = ProcessManager::current_pcb(); 34 35 let mut basic_info = pcb.basic_mut(); 36 // 暂存原本的用户地址空间的引用(因为如果在切换页表之前释放了它，可能会造成内存use after free) 37 let old_address_space = basic_info.user_vm(); 38 39 // 在pcb中原来的用户地址空间 40 unsafe { 41 basic_info.set_user_vm(None); 42 } 43 // 创建新的地址空间并设置为当前地址空间 44 let address_space = AddressSpace::new(true).expect("Failed to create new address space"); 45 unsafe { 46 basic_info.set_user_vm(Some(address_space.clone())); 47 } 48 49 // to avoid deadlock 50 drop(basic_info); 51 52 assert!( 53 AddressSpace::is_current(&address_space), 54 "Failed to set address space" 55 ); 56 // kdebug!("Switch to new address space"); 57 58 // 切换到新的用户地址空间 59 unsafe { address_space.read().user_mapper.utable.make_current() }; 60 61 drop(old_address_space); 62 drop(irq_guard); 63 // kdebug!("to load binary file"); 64 let mut param = ExecParam::new(path.as_str(), address_space.clone(), ExecParamFlags::EXEC); 65 66 // 加载可执行文件 67 let load_result = load_binary_file(&mut param) 68 .unwrap_or_else(|e| panic!("Failed to load binary file: {:?}, path: {:?}", e, path)); 69 // kdebug!("load binary file done"); 70 // kdebug!("argv: {:?}, envp: {:?}", argv, envp); 71 param.init_info_mut().args = argv; 72 param.init_info_mut().envs = envp; 73 74 // 把proc_init_info写到用户栈上 75 76 let (user_sp, argv_ptr) = unsafe { 77 param 78 .init_info() 79 .push_at( 80 address_space 81 .write() 82 .user_stack_mut() 83 .expect("No user stack found"), 84 ) 85 .expect("Failed to push proc_init_info to user stack") 86 }; 87 88 // kdebug!("write proc_init_info to user stack done"); 89 90 // （兼容旧版libc）把argv的指针写到寄存器内 91 // TODO: 改写旧版libc，不再需要这个兼容 92 regs.rdi = param.init_info().args.len() as u64; 93 regs.rsi = argv_ptr.data() as u64; 94 95 // 设置系统调用返回时的寄存器状态 96 // TODO: 中断管理重构后，这里的寄存器状态设置要删掉！！！改为对trap frame的设置。要增加架构抽象。 97 regs.rsp = user_sp.data() as u64; 98 regs.rbp = user_sp.data() as u64; 99 regs.rip = load_result.entry_point().data() as u64; 100 101 regs.cs = USER_CS.bits() as u64; 102 regs.ds = USER_DS.bits() as u64; 103 regs.ss = USER_DS.bits() as u64; 104 regs.es = 0; 105 regs.rflags = 0x200; 106 regs.rax = 1; 107 108 drop(param); 109 110 // kdebug!("regs: {:?}\n", regs); 111 112 // kdebug!( 113 // "tmp_rs_execve: done, load_result.entry_point()={:?}", 114 // load_result.entry_point() 115 // ); 116 117 return Ok(()); 118 } 119 120 /// ## 用于控制和查询与体系结构相关的进程特定选项 121 pub fn arch_prctl(option: usize, arg2: usize) -> Result<usize, SystemError> { 122 let pcb = ProcessManager::current_pcb(); 123 if let Err(SystemError::EINVAL) = Self::do_arch_prctl_64(&pcb, option, arg2, true) { 124 Self::do_arch_prctl_common(option, arg2)?; 125 } 126 Ok(0) 127 } 128 129 /// ## 64位下控制fs/gs base寄存器的方法 130 pub fn do_arch_prctl_64( 131 pcb: &Arc<ProcessControlBlock>, 132 option: usize, 133 arg2: usize, 134 from_user: bool, 135 ) -> Result<usize, SystemError> { 136 let mut arch_info = pcb.arch_info_irqsave(); 137 match option { 138 ARCH_GET_FS => { 139 unsafe { arch_info.save_fsbase() }; 140 let mut writer = UserBufferWriter::new( 141 arg2 as *mut usize, 142 core::mem::size_of::<usize>(), 143 from_user, 144 )?; 145 writer.copy_one_to_user(&arch_info.fsbase, 0)?; 146 } 147 ARCH_GET_GS => { 148 unsafe { arch_info.save_gsbase() }; 149 let mut writer = UserBufferWriter::new( 150 arg2 as *mut usize, 151 core::mem::size_of::<usize>(), 152 from_user, 153 )?; 154 writer.copy_one_to_user(&arch_info.gsbase, 0)?; 155 } 156 ARCH_SET_FS => { 157 arch_info.fsbase = arg2; 158 // 如果是当前进程则直接写入寄存器 159 if pcb.pid() == ProcessManager::current_pcb().pid() { 160 unsafe { arch_info.restore_fsbase() } 161 } 162 } 163 ARCH_SET_GS => { 164 arch_info.gsbase = arg2; 165 if pcb.pid() == ProcessManager::current_pcb().pid() { 166 unsafe { arch_info.restore_gsbase() } 167 } 168 } 169 _ => { 170 return Err(SystemError::EINVAL); 171 } 172 } 173 Ok(0) 174 } 175 176 #[allow(dead_code)] 177 pub fn do_arch_prctl_common(_option: usize, _arg2: usize) -> Result<usize, SystemError> { 178 todo!("do_arch_prctl_common not unimplemented"); 179 } 180 } 181 182 pub const ARCH_SET_GS: usize = 0x1001; 183 pub const ARCH_SET_FS: usize = 0x1002; 184 pub const ARCH_GET_FS: usize = 0x1003; 185 pub const ARCH_GET_GS: usize = 0x1004; 186