microblaze: uaccess: Fix put_user for noMMU
[linux-2.6-block.git] / arch / microblaze / include / asm / uaccess.h
index 1e8fa4b7611545c3525c8db470b3b2472a562ac1..4f17950d0a0e041c28333ac8d7dbe16cd0448d69 100644 (file)
@@ -71,6 +71,9 @@ struct exception_table_entry {
        unsigned long insn, fixup;
 };
 
+/* Returns 0 if exception not found and fixup otherwise.  */
+extern unsigned long search_exception_table(unsigned long);
+
 #ifndef CONFIG_MMU
 
 /* Check against bounds of physical memory */
@@ -108,60 +111,170 @@ static inline int ___range_ok(unsigned long addr, unsigned long size)
 # define __EX_TABLE_SECTION    ".section .discard,\"a\"\n"
 #endif
 
+extern unsigned long __copy_tofrom_user(void __user *to,
+               const void __user *from, unsigned long size);
+
+/* Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail. */
+static inline unsigned long __must_check __clear_user(void __user *to,
+                                                       unsigned long n)
+{
+       /* normal memset with two words to __ex_table */
+       __asm__ __volatile__ (                          \
+                       "1:     sb      r0, %2, r0;"    \
+                       "       addik   %0, %0, -1;"    \
+                       "       bneid   %0, 1b;"        \
+                       "       addik   %2, %2, 1;"     \
+                       "2:                     "       \
+                       __EX_TABLE_SECTION              \
+                       ".word  1b,2b;"                 \
+                       ".previous;"                    \
+               : "=r"(n)                               \
+               : "0"(n), "r"(to)
+       );
+       return n;
+}
+
+static inline unsigned long __must_check clear_user(void __user *to,
+                                                       unsigned long n)
+{
+       might_sleep();
+       if (unlikely(!access_ok(VERIFY_WRITE, to, n)))
+               return n;
+
+       return __clear_user(to, n);
+}
+
 #ifndef CONFIG_MMU
 
-/* Undefined function to trigger linker error */
-extern int bad_user_access_length(void);
-
-/* FIXME this is function for optimalization -> memcpy */
-#define __get_user(var, ptr)                           \
-({                                                     \
-       int __gu_err = 0;                               \
-       switch (sizeof(*(ptr))) {                       \
-       case 1:                                         \
-       case 2:                                         \
-       case 4:                                         \
-               (var) = *(ptr);                         \
-               break;                                  \
-       case 8:                                         \
-               memcpy((void *) &(var), (ptr), 8);      \
-               break;                                  \
-       default:                                        \
-               (var) = 0;                              \
-               __gu_err = __get_user_bad();            \
-               break;                                  \
-       }                                               \
-       __gu_err;                                       \
+extern long __user_bad(void);
+
+#define __get_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)                   \
+       );                                                      \
+})
+
+/**
+ * get_user: - Get a simple variable from user space.
+ * @x:   Variable to store result.
+ * @ptr: Source address, in user space.
+ *
+ * Context: User context only.  This function may sleep.
+ *
+ * This macro copies a single simple variable from user space to kernel
+ * space.  It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and the result of
+ * dereferencing @ptr must be assignable to @x without a cast.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ * On error, the variable @x is set to zero.
+ */
+
+#define __get_user(x, ptr)                                             \
+({                                                                     \
+       unsigned long __gu_val;                                         \
+       /*unsigned long __gu_ptr = (unsigned long)(ptr);*/              \
+       long __gu_err;                                                  \
+       switch (sizeof(*(ptr))) {                                       \
+       case 1:                                                         \
+               __get_user_asm("lbu", (ptr), __gu_val, __gu_err);       \
+               break;                                                  \
+       case 2:                                                         \
+               __get_user_asm("lhu", (ptr), __gu_val, __gu_err);       \
+               break;                                                  \
+       case 4:                                                         \
+               __get_user_asm("lw", (ptr), __gu_val, __gu_err);        \
+               break;                                                  \
+       default:                                                        \
+               /* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\
+       }                                                               \
+       x = (__typeof__(*(ptr))) __gu_val;                              \
+       __gu_err;                                                       \
 })
 
-#define __get_user_bad()       (bad_user_access_length(), (-EFAULT))
 
-/* FIXME is not there defined __pu_val */
-#define __put_user(var, ptr)                                   \
+#define get_user(x, ptr)                                               \
+({                                                                     \
+       access_ok(VERIFY_READ, (ptr), sizeof(*(ptr)))                   \
+               ? __get_user((x), (ptr)) : -EFAULT;                     \
+})
+
+#define __put_user_asm(insn, __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__ (                                  \
+                       "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)    \
+       );                                                      \
 })
 
-#define __put_user_bad()       (bad_user_access_length(), (-EFAULT))
+#define __put_user_asm_8(__gu_ptr, __gu_val, __gu_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(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))
-#define get_user(x, ptr)       __get_user((x), (ptr))
 
 #define copy_to_user(to, from, n)      (memcpy((to), (from), (n)), 0)
 #define copy_from_user(to, from, n)    (memcpy((to), (from), (n)), 0)
@@ -173,29 +286,14 @@ extern int bad_user_access_length(void);
 #define __copy_from_user_inatomic(to, from, n) \
                        (__copy_from_user((to), (from), (n)))
 
-#define __clear_user(addr, n)  (memset((void *)(addr), 0, (n)), 0)
-
-/* stejne s MMU */
-static inline unsigned long clear_user(void *addr, unsigned long size)
-{
-       if (access_ok(VERIFY_WRITE, addr, size))
-               size = __clear_user(addr, size);
-       return size;
-}
-
-/* Returns 0 if exception not found and fixup otherwise.  */
-extern unsigned long search_exception_table(unsigned long);
-
 extern long strncpy_from_user(char *dst, const char *src, long count);
 extern long strnlen_user(const char *src, long count);
 
 #else /* CONFIG_MMU */
 
-/*
- * All the __XXX versions macros/functions below do not perform
- * access checking. It is assumed that the necessary checks have been
- * already performed before the finction (macro) is called.
- */
+/* put_user and get_user macros */
+
+extern long __user_bad(void);
 
 #define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err)     \
 ({                                                             \
@@ -231,18 +329,53 @@ extern long strnlen_user(const char *src, long count);
                __get_user_asm("lw", (ptr), __gu_val, __gu_err);        \
                break;                                                  \
        default:                                                        \
-               __gu_val = 0; __gu_err = -EINVAL;                       \
+               /* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\
        }                                                               \
        x = (__typeof__(*(ptr))) __gu_val;                              \
        __gu_err;                                                       \
 })
 
+/**
+ * get_user: - Get a simple variable from user space.
+ * @x:   Variable to store result.
+ * @ptr: Source address, in user space.
+ *
+ * Context: User context only.  This function may sleep.
+ *
+ * This macro copies a single simple variable from user space to kernel
+ * space.  It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and the result of
+ * dereferencing @ptr must be assignable to @x without a cast.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ * On error, the variable @x is set to zero.
+ */
+
 #define get_user(x, ptr)                                               \
 ({                                                                     \
        access_ok(VERIFY_READ, (ptr), sizeof(*(ptr)))                   \
                ? __get_user((x), (ptr)) : -EFAULT;                     \
 })
 
+/**
+ * put_user: - Write a simple value into user space.
+ * @x:   Value to copy to user space.
+ * @ptr: Destination address, in user space.
+ *
+ * Context: User context only.  This function may sleep.
+ *
+ * This macro copies a single simple value from kernel space to user
+ * space.  It supports simple types like char and int, but not larger
+ * data types like structures or arrays.
+ *
+ * @ptr must have pointer-to-simple-variable type, and @x must be assignable
+ * to the result of dereferencing @ptr.
+ *
+ * Returns zero on success, or -EFAULT on error.
+ */
+
 #define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err)     \
 ({                                                             \
        __asm__ __volatile__ (                                  \
@@ -299,7 +432,7 @@ extern long strnlen_user(const char *src, long count);
                __put_user_asm_8((ptr), __gu_val, __gu_err);            \
                break;                                                  \
        default:                                                        \
-               __gu_err = -EINVAL;                                     \
+               /*__gu_err = -EINVAL;*/ __gu_err = __user_bad();        \
        }                                                               \
        __gu_err;                                                       \
 })
@@ -310,69 +443,56 @@ extern long strnlen_user(const char *src, long count);
                ? __put_user((x), (ptr)) : -EFAULT;                     \
 })
 
-/* Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail. */
-static inline unsigned long __must_check __clear_user(void __user *to,
-                                                       unsigned long n)
+#define __copy_from_user(to, from, n)  \
+       __copy_tofrom_user((__force void __user *)(to), \
+                               (void __user *)(from), (n))
+#define __copy_from_user_inatomic(to, from, n) \
+               copy_from_user((to), (from), (n))
+
+static inline long copy_from_user(void *to,
+               const void __user *from, unsigned long n)
 {
-       /* normal memset with two words to __ex_table */
-       __asm__ __volatile__ (                          \
-                       "1:     sb      r0, %2, r0;"    \
-                       "       addik   %0, %0, -1;"    \
-                       "       bneid   %0, 1b;"        \
-                       "       addik   %2, %2, 1;"     \
-                       "2:                     "       \
-                       __EX_TABLE_SECTION              \
-                       ".word  1b,2b;"                 \
-                       ".previous;"                    \
-               : "=r"(n)                               \
-               : "0"(n), "r"(to)
-       );
-       return n;
+       might_sleep();
+       if (access_ok(VERIFY_READ, from, n))
+               return __copy_from_user(to, from, n);
+       else
+               return n;
 }
 
-static inline unsigned long __must_check clear_user(void __user *to,
-                                                       unsigned long n)
+#define __copy_to_user(to, from, n)    \
+               __copy_tofrom_user((void __user *)(to), \
+                       (__force const void __user *)(from), (n))
+#define __copy_to_user_inatomic(to, from, n)   copy_to_user((to), (from), (n))
+
+static inline long copy_to_user(void __user *to,
+               const void *from, unsigned long n)
 {
        might_sleep();
-       if (unlikely(!access_ok(VERIFY_WRITE, to, n)))
+       if (access_ok(VERIFY_WRITE, to, n))
+               return __copy_to_user(to, from, n);
+       else
                return n;
-
-       return __clear_user(to, n);
 }
 
-#define __copy_from_user(to, from, n)  copy_from_user((to), (from), (n))
-#define __copy_from_user_inatomic(to, from, n) \
-               copy_from_user((to), (from), (n))
-
-#define copy_to_user(to, from, n)                                      \
-       (access_ok(VERIFY_WRITE, (to), (n)) ?                           \
-               __copy_tofrom_user((void __user *)(to),                 \
-                       (__force const void __user *)(from), (n))       \
-               : -EFAULT)
+extern int __strncpy_user(char *to, const char __user *from, int len);
 
-#define __copy_to_user(to, from, n)    copy_to_user((to), (from), (n))
-#define __copy_to_user_inatomic(to, from, n)   copy_to_user((to), (from), (n))
+#define __strncpy_from_user    __strncpy_user
 
-#define copy_from_user(to, from, n)                                    \
-       (access_ok(VERIFY_READ, (from), (n)) ?                          \
-               __copy_tofrom_user((__force void __user *)(to),         \
-                       (void __user *)(from), (n))                     \
-               : -EFAULT)
+static inline long
+strncpy_from_user(char *dst, const char __user *src, long count)
+{
+       if (!access_ok(VERIFY_READ, src, 1))
+               return -EFAULT;
+       return __strncpy_from_user(dst, src, count);
+}
 
-extern int __strncpy_user(char *to, const char __user *from, int len);
 extern int __strnlen_user(const char __user *sstr, int len);
 
-#define strncpy_from_user(to, from, len)       \
-               (access_ok(VERIFY_READ, from, 1) ?      \
-                       __strncpy_user(to, from, len) : -EFAULT)
 #define strnlen_user(str, len) \
                (access_ok(VERIFY_READ, str, 1) ? __strnlen_user(str, len) : 0)
 
 #endif /* CONFIG_MMU */
 
-extern unsigned long __copy_tofrom_user(void __user *to,
-               const void __user *from, unsigned long size);
-
 #endif  /* __ASSEMBLY__ */
 #endif /* __KERNEL__ */