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#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/stddef.h>
#include <asm/hypervisor-ifs/dom0_ops.h>
asmlinkage int sys_iopl(unsigned int new_io_pl)
{
unsigned int old_io_pl = current->thread.io_pl;
dom0_op_t op;
if ( !(start_info.flags & SIF_PRIVILEGED) )
return -EPERM;
if ( new_io_pl > 3 )
return -EINVAL;
/* Need "raw I/O" privileges for direct port access. */
if ( (new_io_pl > old_io_pl) && !capable(CAP_SYS_RAWIO) )
return -EPERM;
/* Maintain OS privileges even if user attempts to relinquish them. */
if ( (new_io_pl == 0) && (start_info.flags & SIF_PRIVILEGED) )
new_io_pl = 1;
/* Change our version of the privilege levels. */
current->thread.io_pl = new_io_pl;
/* Force the change at ring 0. */
op.cmd = DOM0_IOPL;
op.u.iopl.domain = DOMID_SELF;
op.u.iopl.iopl = new_io_pl;
HYPERVISOR_dom0_op(&op);
return 0;
}
asmlinkage int sys_ioperm(unsigned long from, unsigned long num, int turn_on)
{
printk(KERN_INFO "ioperm not fully supported - %s\n",
turn_on ? "set iopl to 3" : "ignore resource release");
return turn_on ? sys_iopl(3) : 0;
}
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