[RFC PATCH v2 1/6] arm64: add type casts to untagged_addr macro

Andrey Konovalov andreyknvl at google.com
Tue Mar 27 09:57:37 PDT 2018


This patch makes the untagged_addr macro accept all kinds of address types
(void *, unsigned long, etc.) and allows not to specify type casts in each
place where it is used. This is done by using __typeof__.

Signed-off-by: Andrey Konovalov <andreyknvl at google.com>
---
 arch/arm64/include/asm/uaccess.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h
index e66b0fca99c2..2d6451cbaa86 100644
--- a/arch/arm64/include/asm/uaccess.h
+++ b/arch/arm64/include/asm/uaccess.h
@@ -102,7 +102,8 @@ static inline unsigned long __range_ok(const void __user *addr, unsigned long si
  * up with a tagged userland pointer. Clear the tag to get a sane pointer to
  * pass on to access_ok(), for instance.
  */
-#define untagged_addr(addr)		sign_extend64(addr, 55)
+#define untagged_addr(addr)		\
+	((__typeof__(addr))sign_extend64((__u64)(addr), 55))
 
 #define access_ok(type, addr, size)	__range_ok(addr, size)
 #define user_addr_max			get_fs
-- 
2.17.0.rc0.231.g781580f067-goog




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