x86: signal: introduce do_rt_sigreturn()

introduce do_rt_sigreturn(), to collect common part of sys_rt_sigreturn().

No change in functionality intended.
Signed-off-by: NHiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

arch/x86/kernel/signal_32.c

@@ -215,9 +215,8 @@ asmlinkage unsigned long sys_sigreturn(unsigned long __unused)
 	return 0;
 }
 
-asmlinkage int sys_rt_sigreturn(unsigned long __unused)
+static long do_rt_sigreturn(struct pt_regs *regs)
 {
-	struct pt_regs *regs = (struct pt_regs *)&__unused;
 	struct rt_sigframe __user *frame;
 	unsigned long ax;
 	sigset_t set;
@@ -243,10 +242,17 @@ asmlinkage int sys_rt_sigreturn(unsigned long __unused)
 	return ax;
 
 badframe:
-	signal_fault(regs, frame, "rt sigreturn");
+	signal_fault(regs, frame, "rt_sigreturn");
 	return 0;
 }
 
+asmlinkage int sys_rt_sigreturn(unsigned long __unused)
+{
+	struct pt_regs *regs = (struct pt_regs *)&__unused;
+
+	return do_rt_sigreturn(regs);
+}
+
 /*
  * Set up a signal frame.
  */

arch/x86/kernel/signal_64.c

@@ -104,11 +104,11 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
 	return err;
 }
 
-asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
+static long do_rt_sigreturn(struct pt_regs *regs)
 {
 	struct rt_sigframe __user *frame;
-	sigset_t set;
 	unsigned long ax;
+	sigset_t set;
 
 	frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long));
 	if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
@@ -131,10 +131,15 @@ asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
 	return ax;
 
 badframe:
-	signal_fault(regs, frame, "sigreturn");
+	signal_fault(regs, frame, "rt_sigreturn");
 	return 0;
 }
 
+asmlinkage long sys_rt_sigreturn(struct pt_regs *regs)
+{
+	return do_rt_sigreturn(regs);
+}
+
 /*
  * Set up a signal frame.
  */