m68k: implement __clear_user()

m68k: implement __clear_user(), which is needed by fs/signalfd.c

Since we always let the MMU do all checking, clear_user() and __clear_user()
are identical. The old clear_user() is renamed to __clear_user() for
consistency.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Davide Libenzi <davidel@xmailserver.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/m68k/lib/uaccess.c

@@ -181,7 +181,7 @@ EXPORT_SYMBOL(strnlen_user);
  * Zero Userspace
  */
 
-unsigned long clear_user(void __user *to, unsigned long n)
+unsigned long __clear_user(void __user *to, unsigned long n)
 {
 	unsigned long res;
 
@@ -219,4 +219,4 @@ unsigned long clear_user(void __user *to, unsigned long n)
 
     return res;
 }
-EXPORT_SYMBOL(clear_user);
+EXPORT_SYMBOL(__clear_user);

include/asm-m68k/uaccess.h

@@ -361,7 +361,9 @@ __constant_copy_to_user(void __user *to, const void *from, unsigned long n)
 
 long strncpy_from_user(char *dst, const char __user *src, long count);
 long strnlen_user(const char __user *src, long n);
-unsigned long clear_user(void __user *to, unsigned long n);
+unsigned long __clear_user(void __user *to, unsigned long n);
+
+#define clear_user	__clear_user
 
 #define strlen_user(str) strnlen_user(str, 32767)