diff --git a/linux/mm/memory.c b/linux/mm/memory.c
index 0fdf229..80b36c7 100644
--- a/linux/mm/memory.c
+++ b/linux/mm/memory.c
@@ -19,13 +19,14 @@
  *
  * Also corrected some "invalidate()"s - I wasn't doing enough of them.
  */
-
+#include <stdarg.h>
 #include <signal.h>
 #include <asm/system.h>
 #include <linux/sched.h>
 #include <linux/head.h>
 #include <linux/kernel.h>
-
+#include <new.h>
+#include <asm/segment.h>
 volatile void do_exit(long code);
 
 static inline volatile void oom(void)
@@ -369,8 +370,8 @@ void do_no_page(unsigned long error_code,unsigned long address)
 	unsigned long page;
 	int block,i;
 
-	if (current->pid > 5)
-		printk(" --do_no_page: address=%x, pid=%d\n", address, current->pid);
+	/* if (current->pid > 5)
+		printk(" --do_no_page: address=%x, pid=%d\n", address, current->pid); */
 		
 	address &= 0xfffff000;
 	tmp = address - current->start_code;
@@ -466,3 +467,375 @@ void calc_mem(void)
 }
 
 
+static int my_share(unsigned long address, struct task_struct * p)
+{
+	unsigned long from;
+	unsigned long to;
+	unsigned long from_page;
+	unsigned long to_page;
+	unsigned long phys_addr;
+
+	from_page = to_page = ((address>>20) & 0xffc);
+	from_page += ((current->start_code>>20) & 0xffc);
+	to_page += ((p->start_code>>20) & 0xffc);
+
+	from = *(unsigned long *) from_page;
+	from &= 0xfffff000;
+	from_page = from + ((address>>10) & 0xffc);
+	phys_addr = *(unsigned long *) from_page;
+	to = *(unsigned long *) to_page;
+	if (!(to & 1))
+		if (to = get_free_page())
+			*(unsigned long *) to_page = to | 7;
+		else
+			return 0;
+	to &= 0xfffff000;
+	to_page = to + ((address>>10) & 0xffc);
+	if (1 & *(unsigned long *) to_page)
+		return 0;
+	/* share them: write-protect */
+	*(unsigned long *) to_page = *(unsigned long *) from_page;
+	phys_addr -= LOW_MEM;
+	phys_addr >>= 12;
+	mem_map[phys_addr]++;
+	return 1;
+}
+
+// rememeber to sync when munmap exit manual 
+
+long sys_mmap(void * start,size_t len,...)// int prot,int flags,int fd,off_t off
+{
+	printk("start mmaping\n");
+	/* va_list args;
+	va_start(args,len); */
+	int prot=3,flags=1,fd=3,off=0;
+	/* prot=va_arg(args,int);flags=va_arg(args,int);fd=va_arg(args,int);
+	off_t off=va_arg(args,off_t);
+	int *ll=&len;printk("%d,%d,%d,%d,%d\n",*ll,*(ll+1),*(ll+2),*(ll+3),*(ll+4));
+	va_end(args);
+	printk("%d,%d,%d,%ld\n",prot,flags,fd,off);
+	 */
+	int block;
+	size_t l=len;
+	struct buffer_head * bh;
+	char *temp,*p1,*p2;
+	void * buf=start;
+	int tempprot=0;
+	
+	//因为new.h和namei.c定义不一样，要修改
+	if(prot &PROT_READ) tempprot |=4;
+	if(prot &PROT_EXEC) tempprot |=1;
+	if(prot &PROT_WRITE) tempprot |=2;
+
+	//特殊量len>0 off%4096==0 prot至少有read权限
+	if( (flags & MAP_SHARED)&& (flags &MAP_PRIVATE )) 
+	{
+		printk("error with private and shared request.\n");
+		return -1;
+	}
+	if(len<=0 ||  off<0 || (off%PAGE_SIZE)) 
+	{
+		if(len<=0) 
+			printk("the len of the wanting bytes must be positive.\n");
+		else
+			printk("offset must be the mul of 4096.\n");
+		return MAP_FAILED;
+	}	
+	if(!(prot& PROT_READ)) return MAP_FAILED;
+
+	//permissions of the file ,搬运函数namei.c::permissions
+	printk("fd: %d\n",fd);
+	struct m_inode *inode=current->filp[fd]->f_inode;
+	printk("end of permissions\n");
+	int mode = inode->i_mode;
+	if (inode->i_dev && !inode->i_nlinks)
+		{printk("end of permissions1\n");return MAP_FAILED;}
+	else if (current->euid==inode->i_uid)
+		mode >>= 6;
+	else if (current->egid==inode->i_gid)
+		mode >>= 3;
+	if (!(((mode & tempprot & 0007) == tempprot) || suser()))
+	{
+		printk("error permission.");
+		return MAP_FAILED;
+	}
+	//end of permission check
+	printk("end of permissions\n");
+	
+	//设置用户空间的虚拟地址，初始为32MB处，这样写在brk增长至32MB时会有bug,我们忽略
+	//同时，当栈向下增长到一定程度时，也会和当前地址冲突，我们忽略
+	if(start<=current->brk || start>=current->start_stack-0x8000 || start==NULL) 
+	{
+		if(!current->mmap_tail)
+			buf=0x2000000;
+		else
+			buf=current->mmap_tail->endaddr;
+	}
+	//申请mmap
+	struct mmap_struct *mmap=(struct mmap_struct *)malloc(sizeof(struct mmap_struct));
+	mmap->address=buf;
+	mmap->size=len;
+	mmap->endaddr=(unsigned long)buf+(len + 0xfff)&0xfffff000;
+	mmap->rw=prot;
+	mmap->ps=flags;
+	mmap->filenode=(struct m_inode*)malloc(sizeof(struct m_inode));
+	memcpy(mmap->filenode,inode,sizeof(struct m_inode));
+	printk("izone[0]:%x:\n",inode->i_zone[0]);
+	if(!mmap->filenode->i_count)mmap->filenode->i_count=1;
+	mmap->off=off;
+	mmap->next=NULL;
+	//加入current->mmap
+	if(!current->mmap) 
+		{current->mmap=current->mmap_tail=mmap;}
+	else {
+		current->mmap_tail->next=mmap;
+		current->mmap_tail=mmap;
+	}
+	printk("buf: %x\n",(unsigned long )buf);
+	
+	//分配物理页
+
+	unsigned long from;
+	unsigned long to;
+	unsigned long from_page;
+	unsigned long to_page;
+	unsigned long phys_addr;
+	unsigned long tpage;
+	unsigned long address=mmap->address;
+	while(address<mmap->endaddr)
+	{
+		from_page =  ((address>>20) & 0xffc);
+		from_page += ((current->start_code>>20) & 0xffc);//页目录
+		if(!(*(unsigned long *)from_page&1))  //页表项不存在，申请页面
+			if(!(tpage=get_free_page()))
+			{
+				printk("out of memory.\n");
+				return MAP_FAILED;
+			}
+			else
+				{
+					*(unsigned long *)from_page= tpage | 7;
+					mem_map[(tpage-LOW_MEM)>>12]++;
+				}
+		from=*(unsigned long *)from_page;	//页表项
+		from &= 0xfffff000;
+		from_page = from + ((address>>10) & 0xffc);
+		if(!(*(unsigned long *)from_page & 1))	//物理页不存在
+			if(!(tpage=get_free_page()))
+			{
+				printk("out of memory.\n");
+				return MAP_FAILED;
+			}
+			else
+			{
+				*(unsigned long *)from_page= tpage | 7; 
+				mem_map[(tpage-LOW_MEM)>>12]++;
+			}
+		*(unsigned long *)from_page &= (prot&PROT_WRITE); //分配读写权限
+		
+		if(flags & MAP_SHARED)
+		{
+			printk("i am doing sharing.");
+			struct task_struct ** p;
+
+			for (p = &LAST_TASK ; p > &FIRST_TASK ; --p) {
+				if (!*p)
+					continue;
+				if (current == *p)
+					continue;
+				//在这一部分,我将current->address处的物理页复制给
+				//所有进程的该区域，可能导致错误，但我们忽略。
+				if(!my_share(address,*p))
+					printk("share failed at task:pid=%d",(*p)->pid);
+			}
+		}
+		address+=PAGE_SIZE;
+	}
+		
+	//read and put in 
+	if (!(block = inode->i_zone[0]))
+		return NULL;
+	if (!(bh = bread(inode->i_dev,block)))
+		return NULL;
+	temp = (char *) bh->b_data;
+	p1=temp+off;p2=buf;
+	while(l--)
+		put_fs_byte(*(p1++),p2++);
+	printk("%s\n",temp+off);
+	return buf;
+}
+static int my_sync(off_t pos, struct m_inode * inode, char * buf, int count)
+{
+	int block,c;
+	struct buffer_head * bh;
+	char * p;
+	int i=0;
+
+	//int block;
+	//struct buffer_head * bh;
+	struct dir_entry * de;
+	int ttp=0;;
+	printk("sync:izone[0]:%x:\n",inode->i_zone[0]);
+	if (!(block = inode->i_zone[0]))
+		return -1;
+	if (!(bh = bread(inode->i_dev,block)))
+		return -1;
+	de=(char*)bh->b_data;
+	for(ttp=0;ttp<count;ttp++)
+	{
+		printk("char:%c,",*(de+ttp));
+	}
+
+	while (i<count) {
+		if (!(block = create_block(inode,pos/BLOCK_SIZE)))
+			break;
+		if (!(bh=bread(inode->i_dev,block)))
+			break;
+		c = pos % BLOCK_SIZE;
+		p = c + bh->b_data;
+		bh->b_dirt = 1;
+		c = BLOCK_SIZE-c;
+		if (c > count-i) c = count-i;
+		pos += c;
+		if (pos > inode->i_size) {
+			inode->i_size = pos;  
+			inode->i_dirt = 1;
+		}
+		i += c;
+		while (c-->0)
+			*(p++) = get_fs_byte(buf++);
+		brelse(bh);
+	}
+	inode->i_mtime = CURRENT_TIME;//文件最后修改时间
+	inode->i_ctime = CURRENT_TIME;//i节点修改时间
+	return (i?i:-1);
+}
+
+
+int sys_munmap(void * start ,size_t size)
+{
+	struct mmap_struct *temp=current->mmap;
+	struct mmap_struct *pre=NULL;
+	while(temp!=NULL)
+	{
+		if(temp->address==(unsigned long)start)
+			break;
+		else temp=temp->next;
+		pre=temp;
+	}
+	if(!temp) 
+	{
+		printk("invalid address.\n");
+		return -1;
+	}
+	if(!pre)
+	{
+		if(current->mmap_tail==current->mmap)current->mmap_tail=NULL;
+		current->mmap==current->mmap->next;
+	}
+	if(temp->next=NULL)
+	{
+		current->mmap_tail=pre;
+		pre->next=NULL;
+	}
+	else{
+		pre->next=temp->next;
+	}
+	printk("addr: %lx,endaddr : %lx\n",temp->address,temp->endaddr);
+	unsigned long from;
+	unsigned long to;
+	unsigned long from_page;
+	unsigned long to_page;
+	unsigned long phys_addr;
+	unsigned long tpage;
+	unsigned long address=temp->address;
+	if(!(temp->ps & MAP_SHARED))
+		goto mytag;
+	//若为共享，执行下面的代码
+	while (address < temp ->endaddr)
+	{
+		printk("addr: %lx\n",address);
+		from_page =  ((address>>20) & 0xffc);
+		from_page += ((current->start_code>>20) & 0xffc);//页目录
+		from=*(unsigned long *)from_page;	//页表项
+		from &= 0xfffff000;
+		from_page = from + ((address>>10) & 0xffc);
+		phys_addr =	(*(unsigned long *)from_page & 0xfffff000);
+		//printk("addr: %lx",*(unsigned long *)from_page);
+		if(!(*(unsigned long *)from_page & 1))
+		{
+			printk("error of deleting page.");
+			return -1;
+		}
+		if(temp->ps & MAP_SHARED)
+		{
+			struct task_struct ** p;
+
+			for (p = &LAST_TASK ; p > &FIRST_TASK ; --p) {
+				if (!*p)
+					continue;
+				if (current == *p)
+					continue;
+				to_page = ((address>>20) & 0xffc)+(((*p)->start_code>>20) & 0xffc);
+				to = *(unsigned long *) to_page;
+				if(!(to & 1))
+					continue;
+				to &= 0xfffff000;
+				to_page = to + ((address>>10) & 0xffc);
+				if(!(*(unsigned long *)to_page &1)) 
+					continue;
+				to = (*(unsigned long *)to_page & 0xfffff000);
+				if(phys_addr == to)
+				{
+					*(unsigned long *)to_page &= ~1;
+					mem_map[(phys_addr-LOW_MEM)>>12]--;
+				}
+			}
+		}
+		address+=PAGE_SIZE;
+	}
+	if(temp->ps & MAP_SHARED)
+	{
+		if(my_sync(temp->off,temp->filenode,(char*)(temp->address),temp->size)==-1)
+			return -1;
+	}
+mytag:
+	//取消物理页写权限
+	while (address < temp ->endaddr)
+	{
+		from_page =  ((address>>20) & 0xffc);
+		from_page += ((current->start_code>>20) & 0xffc);//页目录
+		from=*(unsigned long *)from_page;	//页表项
+		from &= 0xfffff000;
+		from_page = from + ((address>>10) & 0xffc);
+		phys_addr =	(*(unsigned long *)from_page & 0xfffff000);
+		//printk("addr: %lx",*(unsigned long *)from_page);
+		if(!(*(unsigned long *)from_page & 1))
+		{
+			printk("error of deleting page.");
+			return -1;
+		}
+		else{
+			*(unsigned long *)from_page &= ~1;
+		}
+	}
+	int block;
+	struct buffer_head * bh;
+	struct dir_entry * de;
+	int ttp=0;;
+	printk("temp->izone[0]:%x:\n",temp->filenode->i_zone[0]);
+	if (!(block = temp->filenode->i_zone[0]))
+		return -1;
+	if (!(bh = bread(temp->filenode->i_dev,block)))
+		return -1;
+	de=(char*)bh->b_data;
+	for(ttp=0;ttp<temp->size;ttp++)
+	{
+		printk("char:%c,",*(de+ttp));
+	}
+	free(temp);
+	return 0;
+}
+
+
+