[RFC PATCH v1 8/9] arm64: Add unsafe_copy_from_user()

[Christophe Leroy (CS GROUP)]

At the time being, x86 and arm64 are missing unsafe_copy_from_user().

Add it.

Signed-off-by: Christophe Leroy (CS GROUP) <chleroy at kernel.org>
---
 arch/arm64/include/asm/uaccess.h | 29 ++++++++++++++++++++++++-----
 1 file changed, 24 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h
index 1e20ec91b56f..adfdb52cd82b 100644
--- a/arch/arm64/include/asm/uaccess.h
+++ b/arch/arm64/include/asm/uaccess.h
@@ -437,7 +437,7 @@ static inline void user_access_restore(unsigned long enabled) { }
  * We want the unsafe accessors to always be inlined and use
  * the error labels - thus the macro games.
  */
-#define unsafe_copy_loop(dst, src, len, type, label)				\
+#define unsafe_put_loop(dst, src, len, type, label)				\
 	while (len >= sizeof(type)) {						\
 		unsafe_put_user(*(type *)(src),(type __user *)(dst),label);	\
 		dst += sizeof(type);						\
@@ -450,10 +450,29 @@ do {									\
 	char __user *__ucu_dst = (_dst);				\
 	const char *__ucu_src = (_src);					\
 	size_t __ucu_len = (_len);					\
-	unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u64, label);	\
-	unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u32, label);	\
-	unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u16, label);	\
-	unsafe_copy_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label);	\
+	unsafe_put_loop(__ucu_dst, __ucu_src, __ucu_len, u64, label);	\
+	unsafe_put_loop(__ucu_dst, __ucu_src, __ucu_len, u32, label);	\
+	unsafe_put_loop(__ucu_dst, __ucu_src, __ucu_len, u16, label);	\
+	unsafe_put_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label);	\
+} while (0)
+
+#define unsafe_get_loop(dst, src, len, type, label)				\
+	while (len >= sizeof(type)) {						\
+		unsafe_get_user(*(type __user *)(src),(type *)(dst),label);	\
+		dst += sizeof(type);						\
+		src += sizeof(type);						\
+		len -= sizeof(type);						\
+	}
+
+#define unsafe_copy_from_user(_dst,_src,_len,label)			\
+do {									\
+	char *__ucu_dst = (_dst);					\
+	const char __user *__ucu_src = (_src);				\
+	size_t __ucu_len = (_len);					\
+	unsafe_get_loop(__ucu_dst, __ucu_src, __ucu_len, u64, label);	\
+	unsafe_get_loop(__ucu_dst, __ucu_src, __ucu_len, u32, label);	\
+	unsafe_get_loop(__ucu_dst, __ucu_src, __ucu_len, u16, label);	\
+	unsafe_get_loop(__ucu_dst, __ucu_src, __ucu_len, u8, label);	\
 } while (0)
 
 extern unsigned long __must_check __arch_clear_user(void __user *to, unsigned long n);
-- 
2.49.0