1 files changed, 49 insertions, 1 deletions

diff --git a/include/asm-x86/uaccess.h b/include/asm-x86/uaccess.h
index bcda5d075921..4353b2267a02 100644
--- a/include/asm-x86/uaccess.h
+++ b/include/asm-x86/uaccess.h
@@ -233,6 +233,47 @@ do {									\
 
 #endif
 
+#ifdef CONFIG_X86_32
+#define __get_user_asm_u64(x, ptr, retval, errret)      (x) = __get_user_bad()
+#else
+#define __get_user_asm_u64(x, ptr, retval, errret) \
+         __get_user_asm(x, ptr, retval, "q", "", "=r", errret)
+#endif
+
+#define __get_user_size(x, ptr, size, retval, errret)                   \
+do {                                                                    \
+        retval = 0;                                                     \
+        __chk_user_ptr(ptr);                                            \
+        switch (size) {                                                 \
+        case 1:                                                         \
+                __get_user_asm(x, ptr, retval, "b", "b", "=q", errret); \
+                break;                                                  \
+        case 2:                                                         \
+                __get_user_asm(x, ptr, retval, "w", "w", "=r", errret); \
+                break;                                                  \
+        case 4:                                                         \
+                __get_user_asm(x, ptr, retval, "l", "k", "=r", errret); \
+                break;                                                  \
+        case 8:                                                         \
+                __get_user_asm_u64(x, ptr, retval, errret);             \
+                break;                                                  \
+        default:                                                        \
+                (x) = __get_user_bad();                                 \
+        }                                                               \
+} while (0)
+
+#define __get_user_asm(x, addr, err, itype, rtype, ltype, errret)       \
+        asm volatile("1:        mov"itype" %2,%"rtype"1\n"              \
+                     "2:\n"                                             \
+                     ".section .fixup,\"ax\"\n"                         \
+                     "3:        mov %3,%0\n"                            \
+                     "  xor"itype" %"rtype"1,%"rtype"1\n"               \
+                     "  jmp 2b\n"                                       \
+                     ".previous\n"                                      \
+                     _ASM_EXTABLE(1b, 3b)                               \
+                     : "=r" (err), ltype(x)                             \
+                     : "m" (__m(addr)), "i" (errret), "0" (err))
+
 #define __put_user_nocheck(x, ptr, size)                        \
 ({                                                              \
         long __pu_err;                                          \
@@ -240,7 +281,14 @@ do {									\
         __pu_err;                                               \
 })
 
-
+#define __get_user_nocheck(x, ptr, size)                                \
+({                                                                      \
+        long __gu_err;                                                  \
+        unsigned long __gu_val;                                         \
+        __get_user_size(__gu_val, (ptr), (size), __gu_err, -EFAULT);    \
+        (x) = (__force __typeof__(*(ptr)))__gu_val;                     \
+        __gu_err;                                                       \
+})
 
 /* FIXME: this hack is definitely wrong -AK */
 struct __large_struct { unsigned long buf[100]; };