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#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/stddef.h>
asmlinkage int sys_ioperm(unsigned long from, unsigned long num, int turn_on)
{
/* No IO permission! Selective IO perms aren't virtualised yet. */
return -EPERM;
}
asmlinkage int sys_iopl(unsigned long unused)
{
struct pt_regs *regs = (struct pt_regs *)&unused;
unsigned int level = regs->ebx;
unsigned int old = (regs->eflags >> 12) & 3;
if ( !(start_info.flags & SIF_PRIVILEGED) )
return -EPERM;
if ( level > 3 )
return -EINVAL;
if ( (level > old) && !capable(CAP_SYS_RAWIO) )
return -EPERM;
/* Change the one on our stack for sanity's sake. */
regs->eflags = (regs->eflags & 0xffffcfff) | (level << 12);
/* Force the change at ring 0. */
HYPERVISOR_iopl(level);
return 0;
}
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