hexagon: switch to RAW_COPY_USER

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/hexagon/Kconfig

@@ -26,6 +26,7 @@ config HEXAGON
 	select GENERIC_CLOCKEVENTS_BROADCAST
 	select MODULES_USE_ELF_RELA
 	select GENERIC_CPU_DEVICES
+	select ARCH_HAS_RAW_COPY_USER
 	---help---
 	  Qualcomm Hexagon is a processor architecture designed for high
 	  performance and low power across a wide variety of applications.

arch/hexagon/include/asm/uaccess.h

@@ -65,19 +65,12 @@
  */
 
 /*  Assembly somewhat optimized copy routines  */
-unsigned long __copy_from_user_hexagon(void *to, const void __user *from,
+unsigned long raw_copy_from_user(void *to, const void __user *from,
 				     unsigned long n);
-unsigned long __copy_to_user_hexagon(void __user *to, const void *from,
+unsigned long raw_copy_to_user(void __user *to, const void *from,
 				   unsigned long n);
-
-#define __copy_from_user(to, from, n) __copy_from_user_hexagon(to, from, n)
-#define __copy_to_user(to, from, n) __copy_to_user_hexagon(to, from, n)
-
-/*
- * XXX todo: some additonal performance gain is possible by
- * implementing __copy_to/from_user_inatomic, which is much
- * like __copy_to/from_user, but performs slightly less checking.
- */
+#define INLINE_COPY_FROM_USER
+#define INLINE_COPY_TO_USER
 
 __kernel_size_t __clear_user_hexagon(void __user *dest, unsigned long count);
 #define __clear_user(a, s) __clear_user_hexagon((a), (s))
@@ -104,10 +97,14 @@ static inline long hexagon_strncpy_from_user(char *dst, const char __user *src,
 		return -EFAULT;
 
 	if (res > n) {
-		copy_from_user(dst, src, n);
+		long left = raw_copy_from_user(dst, src, n);
+		if (unlikely(left))
+			memset(dst + (n - left), 0, left);
 		return n;
 	} else {
-		copy_from_user(dst, src, res);
+		long left = raw_copy_from_user(dst, src, res);
+		if (unlikely(left))
+			memset(dst + (res - left), 0, left);
 		return res-1;
 	}
 }

arch/hexagon/kernel/hexagon_ksyms.c

@@ -25,8 +25,8 @@
 
 /* Additional functions */
 EXPORT_SYMBOL(__clear_user_hexagon);
-EXPORT_SYMBOL(__copy_from_user_hexagon);
-EXPORT_SYMBOL(__copy_to_user_hexagon);
+EXPORT_SYMBOL(raw_copy_from_user);
+EXPORT_SYMBOL(raw_copy_to_user);
 EXPORT_SYMBOL(__iounmap);
 EXPORT_SYMBOL(__strnlen_user);
 EXPORT_SYMBOL(__vmgetie);

arch/hexagon/mm/copy_from_user.S

@@ -44,7 +44,7 @@
 #define bytes r2
 #define loopcount r5
 
-#define FUNCNAME __copy_from_user_hexagon
+#define FUNCNAME raw_copy_from_user
 #include "copy_user_template.S"
 
 	/* LOAD FAULTS from COPY_FROM_USER */

arch/hexagon/mm/copy_to_user.S

@@ -43,7 +43,7 @@
 #define bytes r2
 #define loopcount r5
 
-#define FUNCNAME __copy_to_user_hexagon
+#define FUNCNAME raw_copy_to_user
 #include "copy_user_template.S"
 
 	/* STORE FAULTS from COPY_TO_USER */