x86: Merge sys_sigaltstack

Change 32-bit sys_sigaltstack to PTREGSCALL2, and merge with 64-bit.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
LKML-Reference: <1260403316-5679-5-git-send-email-brgerst@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/x86/kernel/entry_32.S b/arch/x86/kernel/entry_32.S
index a96a0d8..621ef45 100644
--- a/arch/x86/kernel/entry_32.S
+++ b/arch/x86/kernel/entry_32.S
@@ -763,7 +763,7 @@
 PTREGSCALL0(clone)
 PTREGSCALL0(vfork)
 PTREGSCALL3(execve)
-PTREGSCALL0(sigaltstack)
+PTREGSCALL2(sigaltstack)
 PTREGSCALL0(sigreturn)
 PTREGSCALL0(rt_sigreturn)
 PTREGSCALL0(vm86)
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 74fe6d8..4fd173c 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -545,22 +545,12 @@
 }
 #endif /* CONFIG_X86_32 */
 
-#ifdef CONFIG_X86_32
-int sys_sigaltstack(struct pt_regs *regs)
-{
-	const stack_t __user *uss = (const stack_t __user *)regs->bx;
-	stack_t __user *uoss = (stack_t __user *)regs->cx;
-
-	return do_sigaltstack(uss, uoss, regs->sp);
-}
-#else /* !CONFIG_X86_32 */
-asmlinkage long
+long
 sys_sigaltstack(const stack_t __user *uss, stack_t __user *uoss,
 		struct pt_regs *regs)
 {
 	return do_sigaltstack(uss, uoss, regs->sp);
 }
-#endif /* CONFIG_X86_32 */
 
 /*
  * Do a signal return; undo the signal stack.