x86/compat: Factor out ia32 compat code from compat_arch_ptrace()

Move the ia32-specific code in compat_arch_ptrace() into its
own function.

Signed-off-by: Brian Gerst <brgerst@gmail.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1434974121-32575-6-git-send-email-brgerst@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/kernel/ptrace.c b/arch/x86/kernel/ptrace.c
index 9be72bc..7155957 100644 (file)
--- a/arch/x86/kernel/ptrace.c
+++ b/arch/x86/kernel/ptrace.c
@@ -1123,6 +1123,73 @@ static int genregs32_set(struct task_struct *target,
        return ret;
 }
 
+static long ia32_arch_ptrace(struct task_struct *child, compat_long_t request,
+                            compat_ulong_t caddr, compat_ulong_t cdata)
+{
+       unsigned long addr = caddr;
+       unsigned long data = cdata;
+       void __user *datap = compat_ptr(data);
+       int ret;
+       __u32 val;
+
+       switch (request) {
+       case PTRACE_PEEKUSR:
+               ret = getreg32(child, addr, &val);
+               if (ret == 0)
+                       ret = put_user(val, (__u32 __user *)datap);
+               break;
+
+       case PTRACE_POKEUSR:
+               ret = putreg32(child, addr, data);
+               break;
+
+       case PTRACE_GETREGS:    /* Get all gp regs from the child. */
+               return copy_regset_to_user(child, &user_x86_32_view,
+                                          REGSET_GENERAL,
+                                          0, sizeof(struct user_regs_struct32),
+                                          datap);
+
+       case PTRACE_SETREGS:    /* Set all gp regs in the child. */
+               return copy_regset_from_user(child, &user_x86_32_view,
+                                            REGSET_GENERAL, 0,
+                                            sizeof(struct user_regs_struct32),
+                                            datap);
+
+       case PTRACE_GETFPREGS:  /* Get the child FPU state. */
+               return copy_regset_to_user(child, &user_x86_32_view,
+                                          REGSET_FP, 0,
+                                          sizeof(struct user_i387_ia32_struct),
+                                          datap);
+
+       case PTRACE_SETFPREGS:  /* Set the child FPU state. */
+               return copy_regset_from_user(
+                       child, &user_x86_32_view, REGSET_FP,
+                       0, sizeof(struct user_i387_ia32_struct), datap);
+
+       case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
+               return copy_regset_to_user(child, &user_x86_32_view,
+                                          REGSET_XFP, 0,
+                                          sizeof(struct user32_fxsr_struct),
+                                          datap);
+
+       case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
+               return copy_regset_from_user(child, &user_x86_32_view,
+                                            REGSET_XFP, 0,
+                                            sizeof(struct user32_fxsr_struct),
+                                            datap);
+
+       case PTRACE_GET_THREAD_AREA:
+       case PTRACE_SET_THREAD_AREA:
+               return arch_ptrace(child, request, addr, data);
+
+       default:
+               return compat_ptrace_request(child, request, addr, data);
+       }
+
+       return ret;
+}
+#endif /* CONFIG_IA32_EMULATION */
+
 #ifdef CONFIG_X86_X32_ABI
 static long x32_arch_ptrace(struct task_struct *child,
                            compat_long_t request, compat_ulong_t caddr,
@@ -1211,78 +1278,21 @@ static long x32_arch_ptrace(struct task_struct *child,
 }
 #endif
 
+#ifdef CONFIG_COMPAT
 long compat_arch_ptrace(struct task_struct *child, compat_long_t request,
                        compat_ulong_t caddr, compat_ulong_t cdata)
 {
-       unsigned long addr = caddr;
-       unsigned long data = cdata;
-       void __user *datap = compat_ptr(data);
-       int ret;
-       __u32 val;
-
 #ifdef CONFIG_X86_X32_ABI
        if (!is_ia32_task())
                return x32_arch_ptrace(child, request, caddr, cdata);
 #endif
-
-       switch (request) {
-       case PTRACE_PEEKUSR:
-               ret = getreg32(child, addr, &val);
-               if (ret == 0)
-                       ret = put_user(val, (__u32 __user *)datap);
-               break;
-
-       case PTRACE_POKEUSR:
-               ret = putreg32(child, addr, data);
-               break;
-
-       case PTRACE_GETREGS:    /* Get all gp regs from the child. */
-               return copy_regset_to_user(child, &user_x86_32_view,
-                                          REGSET_GENERAL,
-                                          0, sizeof(struct user_regs_struct32),
-                                          datap);
-
-       case PTRACE_SETREGS:    /* Set all gp regs in the child. */
-               return copy_regset_from_user(child, &user_x86_32_view,
-                                            REGSET_GENERAL, 0,
-                                            sizeof(struct user_regs_struct32),
-                                            datap);
-
-       case PTRACE_GETFPREGS:  /* Get the child FPU state. */
-               return copy_regset_to_user(child, &user_x86_32_view,
-                                          REGSET_FP, 0,
-                                          sizeof(struct user_i387_ia32_struct),
-                                          datap);
-
-       case PTRACE_SETFPREGS:  /* Set the child FPU state. */
-               return copy_regset_from_user(
-                       child, &user_x86_32_view, REGSET_FP,
-                       0, sizeof(struct user_i387_ia32_struct), datap);
-
-       case PTRACE_GETFPXREGS: /* Get the child extended FPU state. */
-               return copy_regset_to_user(child, &user_x86_32_view,
-                                          REGSET_XFP, 0,
-                                          sizeof(struct user32_fxsr_struct),
-                                          datap);
-
-       case PTRACE_SETFPXREGS: /* Set the child extended FPU state. */
-               return copy_regset_from_user(child, &user_x86_32_view,
-                                            REGSET_XFP, 0,
-                                            sizeof(struct user32_fxsr_struct),
-                                            datap);
-
-       case PTRACE_GET_THREAD_AREA:
-       case PTRACE_SET_THREAD_AREA:
-               return arch_ptrace(child, request, addr, data);
-
-       default:
-               return compat_ptrace_request(child, request, addr, data);
-       }
-
-       return ret;
+#ifdef CONFIG_IA32_EMULATION
+       return ia32_arch_ptrace(child, request, caddr, cdata);
+#else
+       return 0;
+#endif
 }
-
-#endif /* CONFIG_IA32_EMULATION */
+#endif /* CONFIG_COMPAT */
 
 #ifdef CONFIG_X86_64