minix/kernel/arch/i386/do_iopenable.c

   1 /* The system call implemented in this file:
   2  *   m_type:    SYS_IOPENABLE
   3  *
   4  * The parameters for this system call are:
   5  *   m_lsys_krn_sys_iopenable.endpt     (process to give I/O Protection Level bits)
   6  *
   7  * Author:
   8  *    Jorrit N. Herder <jnherder@cs.vu.nl>
   9  */
  10
  11 #include "kernel/system.h"
  12 #include <minix/endpoint.h>
  13
  14 #include "arch_proto.h"
  15
  16 /*===========================================================================*
  17  *                              do_iopenable                                 *
  18  *===========================================================================*/
  19 int do_iopenable(struct proc * caller, message * m_ptr)
  20 {
  21   int proc_nr;
  22
  23 #if 1 /* ENABLE_USERPRIV && ENABLE_USERIOPL */
  24   if (m_ptr->m_lsys_krn_sys_iopenable.endpt == SELF) {
  25         okendpt(caller->p_endpoint, &proc_nr);
  26   } else if(!isokendpt(m_ptr->m_lsys_krn_sys_iopenable.endpt, &proc_nr))
  27         return(EINVAL);
  28   enable_iop(proc_addr(proc_nr));
  29   return(OK);
  30 #else
  31   return(EPERM);
  32 #endif
  33 }
  34
  35