x86: signal_32: introduce retcode and rt_retcode

Impact: cleanup

Introduce retcode and rt_retcode to replace setting up frame->retcode.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 24 insertions, 6 deletions

diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index 27a5c8174322..514171ac0d03 100644
--- a/arch/x86/kernel/signal_32.c
+++ b/arch/x86/kernel/signal_32.c
@@ -45,6 +45,28 @@
 # define FIX_EFLAGS     __FIX_EFLAGS
 #endif
 
+static const struct {
+        u16 poplmovl;
+        u32 val;
+        u16 int80;
+} __attribute__((packed)) retcode = {
+        0xb858,         /* popl %eax; movl $..., %eax */
+        __NR_sigreturn,
+        0x80cd,         /* int $0x80 */
+};
+
+static const struct {
+        u8  movl;
+        u32 val;
+        u16 int80;
+        u8  pad;
+} __attribute__((packed)) rt_retcode = {
+        0xb8,           /* movl $..., %eax */
+        __NR_rt_sigreturn,
+        0x80cd,         /* int $0x80 */
+        0
+};
+
 /*
  * Atomically swap in the new signal mask, and wait for a signal.
  */
@@ -427,9 +449,7 @@ __setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
          * reasons and because gdb uses it as a signature to notice
          * signal handler stack frames.
          */
-        err |= __put_user(0xb858, (short __user *)(frame->retcode+0));
-        err |= __put_user(__NR_sigreturn, (int __user *)(frame->retcode+2));
-        err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
+        err |= __put_user(*((u64 *)&retcode), (u64 *)frame->retcode);
 
         if (err)
                 return -EFAULT;
@@ -498,9 +518,7 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
          * reasons and because gdb uses it as a signature to notice
          * signal handler stack frames.
          */
-        err |= __put_user(0xb8, (char __user *)(frame->retcode+0));
-        err |= __put_user(__NR_rt_sigreturn, (int __user *)(frame->retcode+1));
-        err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
+        err |= __put_user(*((u64 *)&rt_retcode), (u64 *)frame->retcode);
 
         if (err)
                 return -EFAULT;