io的一些函数

#define outb(value,port)   __asm__ ("outb %%al,%%dx"::"a" (value),"d" (port))

#define inb(port) ({unsigned char _v; __asm__ volatile ("inb %%dx,%%al":"=a" (_v):"d" (port));_v;})

 

#define outb_p(value,port) \
__asm__ ("outb %%al,%%dx\n" \  

  "\tjmp 1f\n" \  
  "1:\tjmp 1f\n" \
  "1:"::"a" (value),"d" (port))

 

#define inb_p(port) ({ \
unsigned char _v; \ 

__asm__ volatile ("inb %%dx,%%al\n" \
 "\tjmp 1f\n" \
 "1:\tjmp 1f\n" \
 "1:":"=a" (_v):"d" (port)); \
_v; \
})

 

 

#define cli() __asm__("cli\n");

#define sti() __asm__("sti\n");