[PATCH] Make the 32-bit ARM get_user() and put_user() work for 16-bit quantities

[William Cohen]

The 32-bit ARM does not have instructions to perform 16-bit loads or
stores.  The __get_user_asm_half and __put_user_asm_half macros
sythesize those operations.  However, in most cases the pointers
passed into these macros are pointers to 16-bit types and the pointer
arithmetic will end up pointing at the next 16-bit quantity rather
than the second half (byte) of the 16-bit quantity.  The macros need
to explicitly typecast the pointers as pointers to 8-bit quantities to
make the pointer arithmetic work out properly.

Signed-off-by: William Cohen <wcohen at redhat.com>
---
 arch/arm/include/asm/uaccess.h | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h
index 7e1f760..c2d9439 100644
--- a/arch/arm/include/asm/uaccess.h
+++ b/arch/arm/include/asm/uaccess.h
@@ -277,16 +277,16 @@ do {									\
 #define __get_user_asm_half(x,__gu_addr,err)			\
 ({								\
 	unsigned long __b1, __b2;				\
-	__get_user_asm_byte(__b1, __gu_addr, err);		\
-	__get_user_asm_byte(__b2, __gu_addr + 1, err);		\
+	__get_user_asm_byte(__b1, (u8 *)(__gu_addr), err);	\
+	__get_user_asm_byte(__b2, ((u8 *)(__gu_addr)) + 1, err);\
 	(x) = __b1 | (__b2 << 8);				\
 })
 #else
 #define __get_user_asm_half(x,__gu_addr,err)			\
 ({								\
 	unsigned long __b1, __b2;				\
-	__get_user_asm_byte(__b1, __gu_addr, err);		\
-	__get_user_asm_byte(__b2, __gu_addr + 1, err);		\
+	__get_user_asm_byte(__b1, (u8 *)(__gu_addr), err);	\
+	__get_user_asm_byte(__b2, ((u8 *)(__gu_addr)) + 1, err);\
 	(x) = (__b1 << 8) | __b2;				\
 })
 #endif
@@ -358,15 +358,15 @@ do {									\
 #define __put_user_asm_half(x,__pu_addr,err)			\
 ({								\
 	unsigned long __temp = (unsigned long)(x);		\
-	__put_user_asm_byte(__temp, __pu_addr, err);		\
-	__put_user_asm_byte(__temp >> 8, __pu_addr + 1, err);	\
+	__put_user_asm_byte(__temp, (u8 *)(__pu_addr), err);    \
+	__put_user_asm_byte(__temp >> 8, ((u8 *)(__pu_addr)) + 1, err);\
 })
 #else
 #define __put_user_asm_half(x,__pu_addr,err)			\
 ({								\
 	unsigned long __temp = (unsigned long)(x);		\
-	__put_user_asm_byte(__temp >> 8, __pu_addr, err);	\
-	__put_user_asm_byte(__temp, __pu_addr + 1, err);	\
+	__put_user_asm_byte(__temp >> 8, (u8 *)(__pu_addr), err);\
+	__put_user_asm_byte(__temp, ((u8 *)(__pu_addr)) + 1, err);\
 })
 #endif
 
-- 
1.8.3.1