microblaze: uaccess: Fix put_user for noMMU

Here is small regression on dhrystone tests and I think
that on all benchmarking tests. It is due to better checking
mechanism in put_user macro

Signed-off-by: Michal Simek <monstr@monstr.eu>

diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h
index b079ac3..4f17950 100644 (file)
--- a/arch/microblaze/include/asm/uaccess.h
+++ b/arch/microblaze/include/asm/uaccess.h
@@ -213,32 +213,66 @@ extern long __user_bad(void);
                ? __get_user((x), (ptr)) : -EFAULT;                     \
 })
 
-/* Undefined function to trigger linker error */
-extern int bad_user_access_length(void);
+#define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err)     \
+({                                                             \
+       __asm__ __volatile__ (                                  \
+                       "1:"    insn    " %1, %2, r0;"          \
+                       "       addk    %0, r0, r0;"            \
+                       "2:                     "               \
+                       __FIXUP_SECTION                         \
+                       "3:     brid    2b;"                    \
+                       "       addik   %0, r0, %3;"            \
+                       ".previous;"                            \
+                       __EX_TABLE_SECTION                      \
+                       ".word  1b,3b;"                         \
+                       ".previous;"                            \
+               : "=&r"(__gu_err)                               \
+               : "r"(__gu_val), "r"(__gu_ptr), "i"(-EFAULT)    \
+       );                                                      \
+})
 
-/* FIXME is not there defined __pu_val */
-#define __put_user(var, ptr)                                   \
+#define __put_user_asm_8(__gu_ptr, __gu_val, __gu_err)         \
 ({                                                             \
-       int __pu_err = 0;                                       \
-       switch (sizeof(*(ptr))) {                               \
-       case 1:                                                 \
-       case 2:                                                 \
-       case 4:                                                 \
-               *(ptr) = (var);                                 \
-               break;                                          \
-       case 8: {                                               \
-               typeof(*(ptr)) __pu_val = (var);                \
-               memcpy(ptr, &__pu_val, sizeof(__pu_val));       \
-               }                                               \
-               break;                                          \
-       default:                                                \
-               __pu_err = __put_user_bad();                    \
-               break;                                          \
-       }                                                       \
-       __pu_err;                                               \
+       __asm__ __volatile__ (" lwi     %0, %1, 0;"             \
+                       "1:     swi     %0, %2, 0;"             \
+                       "       lwi     %0, %1, 4;"             \
+                       "2:     swi     %0, %2, 4;"             \
+                       "       addk    %0, r0, r0;"            \
+                       "3:                     "               \
+                       __FIXUP_SECTION                         \
+                       "4:     brid    3b;"                    \
+                       "       addik   %0, r0, %3;"            \
+                       ".previous;"                            \
+                       __EX_TABLE_SECTION                      \
+                       ".word  1b,4b,2b,4b;"                   \
+                       ".previous;"                            \
+               : "=&r"(__gu_err)                               \
+               : "r"(&__gu_val), "r"(__gu_ptr), "i"(-EFAULT)   \
+               );                                              \
 })
 
-#define __put_user_bad()       (bad_user_access_length(), (-EFAULT))
+#define __put_user(x, ptr)                                             \
+({                                                                     \
+       __typeof__(*(ptr)) volatile __gu_val = (x);                     \
+       long __gu_err = 0;                                              \
+       switch (sizeof(__gu_val)) {                                     \
+       case 1:                                                         \
+               __put_user_asm("sb", (ptr), __gu_val, __gu_err);        \
+               break;                                                  \
+       case 2:                                                         \
+               __put_user_asm("sh", (ptr), __gu_val, __gu_err);        \
+               break;                                                  \
+       case 4:                                                         \
+               __put_user_asm("sw", (ptr), __gu_val, __gu_err);        \
+               break;                                                  \
+       case 8:                                                         \
+               __put_user_asm_8((ptr), __gu_val, __gu_err);            \
+               break;                                                  \
+       default:                                                        \
+               /*__gu_err = -EINVAL;*/ __gu_err = __user_bad();        \
+       }                                                               \
+       __gu_err;                                                       \
+})
 
 #define put_user(x, ptr)       __put_user((x), (ptr))