x86/vdso: Only define prctl_map_vdso() if CONFIG_CHECKPOINT_RESTORE

[cascardo/linux.git] / arch / x86 / kernel / process_64.c

diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c
index 63236d8..b26a009 100644 (file)
--- a/arch/x86/kernel/process_64.c
+++ b/arch/x86/kernel/process_64.c
@@ -49,6 +49,7 @@
 #include <asm/debugreg.h>
 #include <asm/switch_to.h>
 #include <asm/xen/hypervisor.h>
+#include <asm/vdso.h>
 
 asmlinkage extern void ret_from_fork(void);
 
@@ -524,6 +525,19 @@ void set_personality_ia32(bool x32)
 }
 EXPORT_SYMBOL_GPL(set_personality_ia32);
 
+#ifdef CONFIG_CHECKPOINT_RESTORE
+static long prctl_map_vdso(const struct vdso_image *image, unsigned long addr)
+{
+       int ret;
+
+       ret = map_vdso_once(image, addr);
+       if (ret)
+               return ret;
+
+       return (long)image->size;
+}
+#endif
+
 long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
 {
        int ret = 0;
@@ -577,6 +591,19 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr)
                break;
        }
 
+#ifdef CONFIG_CHECKPOINT_RESTORE
+# ifdef CONFIG_X86_X32
+       case ARCH_MAP_VDSO_X32:
+               return prctl_map_vdso(&vdso_image_x32, addr);
+# endif
+# if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION
+       case ARCH_MAP_VDSO_32:
+               return prctl_map_vdso(&vdso_image_32, addr);
+# endif
+       case ARCH_MAP_VDSO_64:
+               return prctl_map_vdso(&vdso_image_64, addr);
+#endif
+
        default:
                ret = -EINVAL;
                break;