x86: signal: intrroduce get_sigframe() and replace get_sigstack()

Impact: cleanup

Introduce get_sigframe() like 32-bit to replace get_sigstack().
Move the i387 stuff into get_sigframe().

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 e89eaf4..82d37c7 100644 (file)
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -392,10 +392,13 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
  * Determine which stack to use..
  */
 static void __user *
-get_stack(struct k_sigaction *ka, unsigned long sp, unsigned long size)
+get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
+            void __user **fpstate)
 {
-       /* Default to using normal stack - redzone*/
-       sp -= 128;
+       unsigned long sp;
+
+       /* Default to using normal stack - redzone */
+       sp = regs->sp - 128;
 
        /* This is the X/Open sanctioned signal stack switching.  */
        if (ka->sa.sa_flags & SA_ONSTACK) {
@@ -403,7 +406,18 @@ get_stack(struct k_sigaction *ka, unsigned long sp, unsigned long size)
                        sp = current->sas_ss_sp + current->sas_ss_size;
        }
 
-       return (void __user *)round_down(sp - size, 64);
+       if (used_math()) {
+               sp -= sig_xstate_size;
+               *fpstate = (void __user *)round_down(sp, 64);
+               if (save_i387_xstate(*fpstate) < 0)
+                       return (void __user *) -1L;
+
+               sp -= frame_size;
+               return (void __user *)round_down(sp, 16) - 8;
+       }
+
+       sp -= frame_size;
+       return (void __user *)round_down(sp, 64) - 8;
 }
 
 static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
@@ -414,15 +428,7 @@ static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
        int err = 0;
        struct task_struct *me = current;
 
-       if (used_math()) {
-               fp = get_stack(ka, regs->sp, sig_xstate_size);
-               frame = (void __user *)round_down(
-                       (unsigned long)fp - sizeof(struct rt_sigframe), 16) - 8;
-
-               if (save_i387_xstate(fp) < 0)
-                       return -EFAULT;
-       } else
-               frame = get_stack(ka, regs->sp, sizeof(struct rt_sigframe)) - 8;
+       frame = get_sigframe(ka, regs, sizeof(struct rt_sigframe), &fp);
 
        if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
                return -EFAULT;