/****************************************************************** * pthread.c //add by visual 2016.5.26 *系统调用pthread() *******************************************************************/ #include "type.h" #include "const.h" #include "protect.h" #include "string.h" #include "proc.h" #include "global.h" #include "proto.h" static int pthread_pcb_cpy(PROCESS *p_child, PROCESS *p_parent); static int pthread_update_info(PROCESS *p_child, PROCESS *p_parent); static int pthread_stack_init(PROCESS *p_child, PROCESS *p_parent); static int pthread_heap_init(PROCESS *p_child, PROCESS *p_parent); /********************************************************** * sys_pthread //add by visual 2016.5.25 *系统调用sys_pthread的具体实现部分 *************************************************************/ int sys_pthread(void *entry) { PROCESS *p_child; char *p_reg; // point to a register in the new kernel stack, added by xw, 17/12/11 /*if(p_proc_current->task.info.type == TYPE_THREAD ) {//线程不能创建线程 printf("\x1b[31;47m[pthread failed:"); printf(p_proc_current->task.p_name); printf("]\x1b[m"); return -1; }*/ /*****************申请空白PCB表**********************/ p_child = alloc_PCB(); if (0 == p_child) { printf("\x1b[31;47mPCB NULL,pthread faild!\x1b[m"); return -1; } else { PROCESS *p_parent; if (p_proc_current->task.info.type == TYPE_THREAD) { // 线程 p_parent = &(proc_table[p_proc_current->task.info.ppid]); // 父进程 } else { // 进程 p_parent = p_proc_current; // 父进程就是父线程 } /************复制父进程的PCB部分内容（保留了自己的标识信息,但cr3使用的是父进程的）**************/ pthread_pcb_cpy(p_child, p_parent); /************在父进程的栈中分配子线程的栈（从进程栈的低地址分配8M,注意方向）**********************/ pthread_stack_init(p_child, p_parent); /**************初始化子线程的堆（此时的这两个变量已经变成了指针）***********************/ pthread_heap_init(p_child, p_parent); /********************设置线程的执行入口**********************************************/ p_child->task.regs.eip = (u32)entry; p_reg = (char *)(p_child + 1); // added by xw, 17/12/11 *((u32 *)(p_reg + EIPREG - P_STACKTOP)) = p_child->task.regs.eip; // added by xw, 17/12/11 /**************更新进程树标识info信息************************/ pthread_update_info(p_child, p_parent); /************修改子进程的名字***************/ strcpy(p_child->task.p_name, "pthread"); // 所有的子进程都叫pthread /*************子进程返回值在其eax寄存器***************/ p_child->task.regs.eax = 0; // return child with 0 p_reg = (char *)(p_child + 1); // added by xw, 17/12/11 *((u32 *)(p_reg + EAXREG - P_STACKTOP)) = p_child->task.regs.eax; // added by xw, 17/12/11 /****************用户进程数+1****************************/ u_proc_sum += 1; printf("\x1b[32;47m[pthread success:"); printf(p_proc_current->task.p_name); printf("]\x1b[m"); // anything child need is prepared now, set its state to ready. added by xw, 17/12/11 p_child->task.stat = READY; } return p_child->task.pid; } /********************************************************** * pthread_pcb_cpy //add by visual 2016.5.26 *复制父进程PCB表，但是又马上恢复了子进程的标识信息 *************************************************************/ static int pthread_pcb_cpy(PROCESS *p_child, PROCESS *p_parent) { int pid; u32 eflags, selector_ldt; char *p_reg; // point to a register in the new kernel stack, added by xw, 17/12/11 char *esp_save_int, *esp_save_context; // use to save corresponding field in child's PCB, xw, 18/4/21 // 暂存标识信息 pid = p_child->task.pid; // eflags = p_child->task.regs.eflags; //deleted by xw, 17/12/11 p_reg = (char *)(p_child + 1); // added by xw, 17/12/11 eflags = *((u32 *)(p_reg + EFLAGSREG - P_STACKTOP)); // added by xw, 17/12/11 selector_ldt = p_child->task.ldt_sel; // 复制PCB内容 // modified by xw, 17/12/11 // modified begin //*p_child = *p_parent; // esp_save_int and esp_save_context must be saved, because the child and the parent // use different kernel stack! And these two are importent to the child's initial running. // Added by xw, 18/4/21 esp_save_int = p_child->task.esp_save_int; esp_save_context = p_child->task.esp_save_context; p_child->task = p_parent->task; // note that syscalls can be interrupted now! the state of child can only be setted // READY when anything else is well prepared. if an interruption happens right here, // an error will still occur. p_child->task.stat = IDLE; p_child->task.esp_save_int = esp_save_int; // esp_save_int of child must be restored!! p_child->task.esp_save_context = esp_save_context; // same above memcpy(((char *)(p_child + 1) - P_STACKTOP), ((char *)(p_parent + 1) - P_STACKTOP), 18 * 4); // modified end // 恢复标识信息 p_child->task.pid = pid; // p_child->task.regs.eflags = eflags; p_reg = (char *)(p_child + 1); // added by xw, 17/12/11 *((u32 *)(p_reg + EFLAGSREG - P_STACKTOP)) = eflags; // added by xw, 17/12/11 p_child->task.ldt_sel = selector_ldt; return 0; } /********************************************************** * pthread_update_info //add by visual 2016.5.26 *更新父进程和子线程程的进程树标识info *************************************************************/ static int pthread_update_info(PROCESS *p_child, PROCESS *p_parent) { /************更新父进程的info***************/ // 注意 父进程 父进程 父进程 if (p_parent != p_proc_current) { // 只有在线程创建线程的时候才会执行 ，p_parent事实上是父进程 p_parent->task.info.child_t_num += 1; // 子线程数量 p_parent->task.info.child_thread[p_parent->task.info.child_t_num - 1] = p_child->task.pid; // 子线程列表 } /************更新父线程的info**************/ // p_proc_current->task.info.type; //当前是进程还是线程 // p_proc_current->task.info.real_ppid; //亲父进程，创建它的那个进程 // p_proc_current->task.info.ppid; //当前父进程 // p_proc_current->task.info.child_p_num += 1; //子进程数量 // p_proc_current->task.info.child_process[p_proc_current->task.info.child_p_num-1] = p_child->task.pid;//子进程列表 p_proc_current->task.info.child_t_num += 1; // 子线程数量 p_proc_current->task.info.child_thread[p_proc_current->task.info.child_t_num - 1] = p_child->task.pid; // 子线程列表 // p_proc_current->task.text_hold; //是否拥有代码 // p_proc_current->task.data_hold; //是否拥有数据 /************更新子线程的info***************/ p_child->task.info.type = TYPE_THREAD; // 这是一个线程 p_child->task.info.real_ppid = p_proc_current->task.pid; // 亲父进程，创建它的那个线程，注意，这个是创建它的那个线程p_proc_current p_child->task.info.ppid = p_parent->task.pid; // 当前父进程 p_child->task.info.child_p_num = 0; // 子进程数量 // p_child->task.info.child_process[NR_CHILD_MAX] = pid;//子进程列表 p_child->task.info.child_t_num = 0; // 子线程数量 // p_child->task.info.child_thread[NR_CHILD_MAX];//子线程列表 p_child->task.info.text_hold = 0; // 是否拥有代码，子进程不拥有代码 p_child->task.info.data_hold = 0; // 是否拥有数据，子进程拥有数据 return 0; } /********************************************************** * pthread_stack_init //add by visual 2016.5.26 *申请子线程的栈，并重置其esp *************************************************************/ static int pthread_stack_init(PROCESS *p_child, PROCESS *p_parent) { int addr_lin; char *p_reg; // point to a register in the new kernel stack, added by xw, 17/12/11 p_child->task.memmap.stack_lin_limit = p_parent->task.memmap.stack_child_limit; // 子线程的栈界 p_parent->task.memmap.stack_child_limit += 0x4000; // 分配16K p_child->task.memmap.stack_lin_base = p_parent->task.memmap.stack_child_limit - num_4B; // 子线程的基址 for (addr_lin = p_child->task.memmap.stack_lin_base; addr_lin > p_child->task.memmap.stack_lin_limit; addr_lin -= num_4K) // 申请物理地址 lin_mapping_phy(addr_lin, MAX_UNSIGNED_INT, p_child->task.pid, PG_P | PG_USU | PG_RWW, PG_P | PG_USU | PG_RWW); p_child->task.regs.esp = p_child->task.memmap.stack_lin_base; // 调整esp p_reg = (char *)(p_child + 1); // added by xw, 17/12/11 *((u32 *)(p_reg + ESPREG - P_STACKTOP)) = p_child->task.regs.esp; // added by xw, 17/12/11 return 0; } /********************************************************** * pthread_stack_init //add by visual 2016.5.26 *子线程使用父进程的堆 *************************************************************/ static int pthread_heap_init(PROCESS *p_child, PROCESS *p_parent) { p_child->task.memmap.heap_lin_base = (u32) & (p_parent->task.memmap.heap_lin_base); p_child->task.memmap.heap_lin_limit = (u32) & (p_parent->task.memmap.heap_lin_limit); return 0; }