x86: signal: introduce helper align_sigframe()
Impact: cleanup
Introduce helper align_sigframe() to align stack pointer for signal frame.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 53425c6..dde3f2a 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -191,6 +191,20 @@
/*
* Determine which stack to use..
*/
+static unsigned long align_sigframe(unsigned long sp)
+{
+#ifdef CONFIG_X86_32
+ /*
+ * Align the stack pointer according to the i386 ABI,
+ * i.e. so that on function entry ((sp + 4) & 15) == 0.
+ */
+ sp = ((sp + 4) & -16ul) - 4;
+#else /* !CONFIG_X86_32 */
+ sp = round_down(sp, 16) - 8;
+#endif
+ return sp;
+}
+
static inline void __user *
get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
void __user **fpstate)
@@ -236,18 +250,7 @@
return (void __user *)-1L;
}
- sp -= frame_size;
-#ifdef CONFIG_X86_32
- /*
- * Align the stack pointer according to the i386 ABI,
- * i.e. so that on function entry ((sp + 4) & 15) == 0.
- */
- sp = ((sp + 4) & -16ul) - 4;
-#else /* !CONFIG_X86_32 */
- sp = round_down(sp, 16) - 8;
-#endif
-
- return (void __user *) sp;
+ return (void __user *)align_sigframe(sp - frame_size);
}
#ifdef CONFIG_X86_32