arch/arm/kernel/ioport.c

   1 /*
   2  * linux/arch/arm/kernel/ioport.c
   3  *
   4  * IO permission support for ARM.
   5  */
   6
   7 #include <linux/config.h>
   8 #include <linux/sched.h>
   9 #include <linux/kernel.h>
  10 #include <linux/errno.h>
  11 #include <linux/types.h>
  12 #include <linux/ioport.h>
  13 #include <linux/mm.h>
  14
  15 #include <asm/pgtable.h>
  16 #include <asm/uaccess.h>
  17
  18 #ifdef CONFIG_CPU_32
  19 asmlinkage int sys_iopl(unsigned long turn_on)
  20 {
  21         if (turn_on && !capable(CAP_SYS_RAWIO))
  22                 return -EPERM;
  23
  24         /*
  25          * We only support an on_off approach
  26          */
  27         modify_domain(DOMAIN_IO, turn_on ? DOMAIN_MANAGER : DOMAIN_CLIENT);
  28
  29         return 0;
  30 }
  31 #else
  32 asmlinkage int sys_iopl(unsigned long turn_on)
  33 {
  34         return -ENOSYS;
  35 }
  36 #endif