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x86: refactor ioport unification 

Refactor ioport unification to pull out common code.

Cc: mboton@gmail.com
Cc: Kevin Winchester <kjwinchester@gmail.com>
Cc: Zach Brown <zach.brown@oracle.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
This commit is contained in:
Chris Wright 2008-01-30 13:33:10 +01:00 committed by Ingo Molnar
parent 9718769d29
commit a1bf250a6f
1 changed files with 24 additions and 22 deletions
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46
arch/x86/kernel/ioport.c
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@ -113,40 +113,42 @@ asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int turn_on)
* on system-call entry - see also fork() and the signal handling
* code.
*/
static int do_iopl(unsigned int level, struct pt_regs *regs)
{
unsigned int old = (regs->flags >> 12) & 3;
if (level > 3)
return -EINVAL;
/* Trying to gain more privileges? */
if (level > old) {
if (!capable(CAP_SYS_RAWIO))
return -EPERM;
}
regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12);
return 0;
}
#ifdef CONFIG_X86_32
asmlinkage long sys_iopl(unsigned long regsp)
{
struct pt_regs *regs = (struct pt_regs *)&regsp;
unsigned int level = regs->bx;
unsigned int old = (regs->flags >> 12) & 3;
struct thread_struct *t = &current->thread;
int rc;
rc = do_iopl(level, regs);
if (rc < 0)
goto out;
if (level > 3)
return -EINVAL;
/* Trying to gain more privileges? */
if (level > old) {
if (!capable(CAP_SYS_RAWIO))
return -EPERM;
}
t->iopl = level << 12;
regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12);
set_iopl_mask(t->iopl);
return 0;
out:
return rc;
}
#else
asmlinkage long sys_iopl(unsigned int level, struct pt_regs *regs)
{
unsigned int old = (regs->flags >> 12) & 3;
if (level > 3)
return -EINVAL;
/* Trying to gain more privileges? */
if (level > old) {
if (!capable(CAP_SYS_RAWIO))
return -EPERM;
}
regs->flags = (regs->flags & ~X86_EFLAGS_IOPL) | (level << 12);
return 0;
return do_iopl(level, regs);
}
#endif