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>

diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index 27a5c81..514171a 100644 (file)
--- 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;