linux安全第二周总结

/*
*linux/mykernel/myinterrupt.c
*
*Kernelinternalmy_timer_handler
*
*Copyright(C)2013Mengning
*
*/
#include<linux/types.h>
#include<linux/string.h>
#include<linux/ctype.h>
#include<linux/tty.h>
#include<linux/vmalloc.h>

#include"mypcb.h"

externtPCBtask[MAX_TASK_NUM];
externtPCB*my_current_task;
externvolatileintmy_need_sched;
volatileinttime_count=0;

/*
*Calledbytimerinterrupt.
*itrunsinthenameofcurrentrunningprocess,
*soitusekernelstackofcurrentrunningprocess
*/
voidmy_timer_handler(void)
{
#if1
if(time_count%1000==0&&my_need_sched!=1)
{
printk(KERN_NOTICE">>>my_timer_handlerhere<<<\n");
my_need_sched=1;
}
time_count++;
#endif
return;
}

voidmy_schedule(void)
{
tPCB*next;
tPCB*prev;

if(my_current_task==NULL
||my_current_task->next==NULL)
{
return;
}
printk(KERN_NOTICE">>>my_schedule<<<\n");
/*schedule*/
next=my_current_task->next;
prev=my_current_task;
if(next->state==0)/*-1unrunnable,0runnable,>0stopped*/
{
/*switchtonextprocess*/
asmvolatile(
"pushl%%ebp\n\t"/*saveebp*/
"movl%%esp,%0\n\t"/*saveesp*/
"movl%2,%%esp\n\t"/*restoreesp*/
"movl$1f,%1\n\t"/*saveeip*/
"pushl%3\n\t"
"ret\n\t"/*restoreeip*/
"1:\t"/*nextprocessstarthere*/
"popl%%ebp\n\t"
:"=m"(prev->thread.sp),"=m"(prev->thread.ip)
:"m"(next->thread.sp),"m"(next->thread.ip)
);
my_current_task=next;
printk(KERN_NOTICE">>>switch%dto%d<<<\n",prev->pid,next->pid);
}
else
{
next->state=0;
my_current_task=next;
printk(KERN_NOTICE">>>switch%dto%d<<<\n",prev->pid,next->pid);
/*switchtonewprocess*/
asmvolatile(
"pushl%%ebp\n\t"/*saveebp*/
"movl%%esp,%0\n\t"/*saveesp*/
"movl%2,%%esp\n\t"/*restoreesp*/
"movl%2,%%ebp\n\t"/*restoreebp*/
"movl$1f,%1\n\t"/*saveeip*/
"pushl%3\n\t"
"ret\n\t"/*restoreeip*/
:"=m"(prev->thread.sp),"=m"(prev->thread.ip)
:"m"(next->thread.sp),"m"(next->thread.ip)
);
}
return;
}