From 5f083315ba9315d91a9c55c8da7a001a1fb01a9e Mon Sep 17 00:00:00 2001 From: ph649mxes <1347377011@qq.com> Date: Fri, 1 Jul 2022 09:29:35 +0800 Subject: [PATCH] Delete 'fork.c(detailed)' --- fork.c(detailed) | 256 ----------------------------------------------- 1 file changed, 256 deletions(-) delete mode 100644 fork.c(detailed) diff --git a/fork.c(detailed) b/fork.c(detailed) deleted file mode 100644 index 3b47106..0000000 --- a/fork.c(detailed) +++ /dev/null @@ -1,256 +0,0 @@ -/* - * linux/kernel/fork.c - * - * (C) 1991 Linus Torvalds - */ - - /* - * 'fork.c' contains the help-routines for the 'fork' system call - * (see also system_call.s), and some misc functions ('verify_area'). - * Fork is rather simple, once you get the hang of it, but the memory - * management can be a bitch. See 'mm/mm.c': 'copy_page_tables()' - */ -#include - -#include -#include -#include -#include - /*****************************/ -#include -/*****************************/ - -extern void write_verify(unsigned long address); - -long last_pid = 0; - -void verify_area(void* addr, int size) -{ - unsigned long start; - - start = (unsigned long)addr; - size += start & 0xfff; - start &= 0xfffff000; - start += get_base(current->ldt[2]); - while (size > 0) { - size -= 4096; - write_verify(start); - start += 4096; - } -} - -int copy_mem(int nr, struct task_struct* p) -{ - unsigned long old_data_base, new_data_base, data_limit; - unsigned long old_code_base, new_code_base, code_limit; - - code_limit = get_limit(0x0f); - data_limit = get_limit(0x17); - old_code_base = get_base(current->ldt[1]); - old_data_base = get_base(current->ldt[2]); - if (old_data_base != old_code_base) - panic("We don't support separate I&D"); - if (data_limit < code_limit) - panic("Bad data_limit"); - new_data_base = new_code_base = nr * 0x4000000; - p->start_code = new_code_base; - set_base(p->ldt[1], new_code_base); - set_base(p->ldt[2], new_data_base); - if (copy_page_tables(old_data_base, new_data_base, data_limit)) { - printk("free_page_tables: from copy_mem\n"); - free_page_tables(new_data_base, data_limit); - return -ENOMEM; - } - return 0; -} - -/* - * Ok, this is the main fork-routine. It copies the system process - * information (task[nr]) and sets up the necessary registers. It - * also copies the data segment in it's entirety. - */ -int copy_process(int nr, long ebp, long edi, long esi, long gs, long none, - long ebx, long ecx, long edx, - long fs, long es, long ds, - long eip, long cs, long eflags, long esp, long ss) -{ - struct task_struct* p; - int i; - struct file* f; - - p = (struct task_struct*)get_free_page(); - if (!p) - return -EAGAIN; - task[nr] = p; - __asm__ volatile ("cld"); - *p = *current; /* NOTE! this doesn't copy the supervisor stack */ - p->state = TASK_UNINTERRUPTIBLE; - p->pid = last_pid; - p->father = current->pid; - p->counter = p->priority; - p->signal = 0; - p->alarm = 0; - p->leader = 0; /* process leadership doesn't inherit */ - p->utime = p->stime = 0; - p->cutime = p->cstime = 0; - p->start_time = jiffies; - p->tss.back_link = 0; - p->tss.esp0 = PAGE_SIZE + (long)p; - p->tss.ss0 = 0x10; - p->tss.eip = eip; - p->tss.eflags = eflags; - p->tss.eax = 0; - p->tss.ecx = ecx; - p->tss.edx = edx; - p->tss.ebx = ebx; - p->tss.esp = esp; - p->tss.ebp = ebp; - p->tss.esi = esi; - p->tss.edi = edi; - p->tss.es = es & 0xffff; - p->tss.cs = cs & 0xffff; - p->tss.ss = ss & 0xffff; - p->tss.ds = ds & 0xffff; - p->tss.fs = fs & 0xffff; - p->tss.gs = gs & 0xffff; - p->tss.ldt = _LDT(nr); - p->tss.trace_bitmap = 0x80000000; - if (last_task_used_math == current) - __asm__("clts ; fnsave %0"::"m" (p->tss.i387)); - if (copy_mem(nr, p)) { - task[nr] = NULL; - free_page((long)p); - return -EAGAIN; - } - for (i = 0; i < NR_OPEN; i++) - if (f = p->filp[i]) - f->f_count++; - if (current->pwd) - current->pwd->i_count++; - if (current->root) - current->root->i_count++; - if (current->executable) - current->executable->i_count++; - set_tss_desc(gdt + (nr << 1) + FIRST_TSS_ENTRY, &(p->tss)); - set_ldt_desc(gdt + (nr << 1) + FIRST_LDT_ENTRY, &(p->ldt)); - p->state = TASK_RUNNING; /* do this last, just in case */ - return last_pid; -} - -int find_empty_process(void) -{ - int i; - -repeat: - if ((++last_pid) < 0) last_pid = 1; - for (i = 0; i < NR_TASKS; i++) - if (task[i] && task[i]->pid == last_pid) goto repeat; - for (i = 1; i < NR_TASKS; i++) - if (!task[i]) - return i; - return -EAGAIN; -} - -int sys_pthread_attr_init(pthread_attr_t* attr) /* ϵͳ����pthread_attr_initʵ�ֺ��� */ -{ - if (!attr) - { - printk("Error:init pthread failed!\n"); - sys_exit(0); - } - - attr->state = 0; - attr->stackaddr = get_base(current->ldt[1]) + current->brk + PAGE_SIZE; - attr->stacksize = PAGE_SIZE; - - return 0; -} - -int thread_create(int nr, long ebp, long edi, long esi, long gs, long none, - long ebx, long ecx, long edx, - long fs, long es, long ds, - long eip, long cs, long eflags, long esp, long ss) -{ - struct task_struct* p; - int i; - struct file* f; - /*******************************************/ - long func_addr = ecx; /* ecx�д洢�����̴߳������е���ʼ��ַ��edx�д洢���Ǵ��ݸ��̵߳IJ��� */ - long func_arg = edx; - /*******************************************/ - p = (struct task_struct*)get_free_page(); /*����һҳ����TCB*/ - if (!p) - return -EAGAIN; - task[nr] = p; - *p = *current; /* NOTE! this doesn't copy the supervisor stack */ - /*******************************************/ - current->brk = current->brk + PAGE_SIZE; /*����ͬһ�����ڵ��̹߳������Ե�ַ�ռ䣬������Ҫ����TCB�ĵ�ַ�Լ���ջ��ʼ��ַ*/ - p->start_stack = current->brk; - /*******************************************/ - p->state = TASK_UNINTERRUPTIBLE; - p->pid = last_pid; - p->father = current->pid; - p->counter = p->priority; - p->signal = 0; - p->alarm = 0; - p->leader = 0; /* process leadership doesn't inherit */ - p->utime = p->stime = 0; - p->cutime = p->cstime = 0; - p->start_time = jiffies; - - p->tss.back_link = 0; - p->tss.esp0 = PAGE_SIZE + (long)p; - p->tss.ss0 = 0x10; - /*********************************************/ - p->tss.eip = func_addr; /* ecx�д洢�����̴߳������п�ʼִ�еĵ�ַ */ - /*********************************************/ - p->tss.eflags = eflags; - p->tss.eax = 0; - p->tss.ecx = ecx; - p->tss.edx = edx; - p->tss.ebx = ebx; - /*********************************************/ - p->tss.esp = current->brk; /* ջ��ָ��Ӧ�ȳ�ʼ��ΪΪ�̶߳�ջ����ʼ��ַ */ - /*********************************************/ - p->tss.ebp = ebp; - p->tss.esi = esi; - p->tss.edi = edi; - p->tss.es = es & 0xffff; - p->tss.cs = cs & 0xffff; - p->tss.ss = ss & 0xffff; - p->tss.ds = ds & 0xffff; - p->tss.fs = fs & 0xffff; - p->tss.gs = gs & 0xffff; - /*********************************************/ - p->tss.ldt = current->tss.ldt; /* �����߳���Ҫ�����߳�ldt��ַ��Ϊ�����̵�ldt��ַ */ - /*********************************************/ - p->tss.trace_bitmap = 0x80000000; - - if (last_task_used_math == current) - __asm__("clts ; fnsave %0"::"m" (p->tss.i387)); - if (copy_mem(nr, p)) { - task[nr] = NULL; - free_page((long)p); - return -EAGAIN; - } - /*********************************************/ - put_fs_long(func_arg, p->tss.esp); /* ��edx�д�ŵIJ������浽���̵߳Ķ�ջ���� */ - p->tss.esp -= 4; /* �����˶�ջָ����������ƶ��ĸ��ֽڣ��Դ�ŷ��ص�ַ */ - /*********************************************/ - - for (i = 0; i < NR_OPEN; i++) - if ((f = p->filp[i])) - f->f_count++; - if (current->pwd) - current->pwd->i_count++; - if (current->root) - current->root->i_count++; - if (current->executable) - current->executable->i_count++; - - set_tss_desc(gdt + (nr << 1) + FIRST_TSS_ENTRY, &(p->tss)); - set_ldt_desc(gdt + (nr << 1) + FIRST_LDT_ENTRY, &(p->ldt)); - p->state = TASK_RUNNING; - - return p->pid; -}