[PATCH 3/3] nds32: Extract the checking and getting pointer to a macro

From: Zong Li
Date: Mon Aug 13 2018 - 05:27:30 EST


Signed-off-by: Zong Li <zong@xxxxxxxxxxxxx>
---
arch/nds32/include/asm/uaccess.h | 80 ++++++++++++++++++++--------------------
1 file changed, 41 insertions(+), 39 deletions(-)

diff --git a/arch/nds32/include/asm/uaccess.h b/arch/nds32/include/asm/uaccess.h
index e1a2b5b..362a32d 100644
--- a/arch/nds32/include/asm/uaccess.h
+++ b/arch/nds32/include/asm/uaccess.h
@@ -75,54 +75,54 @@ static inline void set_fs(mm_segment_t fs)
* versions are void (ie, don't return a value as such).
*/

-#define get_user(x, ptr) \
-({ \
- long __e = -EFAULT; \
- const __typeof__(*(ptr)) __user *__p = (ptr); \
- if (likely(access_ok(VERIFY_READ, __p, sizeof(*__p)))) { \
- __e = __get_user(x, __p); \
- } else { \
- (x) = 0; \
- } \
- __e; \
-})
+#define get_user __get_user \

#define __get_user(x, ptr) \
({ \
long __gu_err = 0; \
- __get_user_err((x), (ptr), __gu_err); \
+ __get_user_check((x), (ptr), __gu_err); \
__gu_err; \
})

#define __get_user_error(x, ptr, err) \
({ \
- __get_user_err((x), (ptr), err); \
+ __get_user_check((x), (ptr), (err)); \
(void)0; \
})

+#define __get_user_check(x, ptr, err) \
+({ \
+ const __typeof__(*(ptr)) __user *__p = (ptr); \
+ might_fault(); \
+ if (access_ok(VERIFY_READ, __p, sizeof(*__p))) { \
+ __get_user_err((x), __p, (err)); \
+ } else { \
+ (x) = 0; (err) = -EFAULT; \
+ } \
+})
+
#define __get_user_err(x, ptr, err) \
do { \
- const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
unsigned long __gu_val; \
- __chk_user_ptr(__gu_addr); \
- switch (sizeof(*(__gu_addr))) { \
+ __chk_user_ptr(ptr); \
+ switch (sizeof(*(ptr))) { \
case 1: \
- __get_user_asm("lbi", __gu_val, __gu_addr, (err)); \
+ __get_user_asm("lbi", __gu_val, (ptr), (err)); \
break; \
case 2: \
- __get_user_asm("lhi", __gu_val, __gu_addr, (err)); \
+ __get_user_asm("lhi", __gu_val, (ptr), (err)); \
break; \
case 4: \
- __get_user_asm("lwi", __gu_val, __gu_addr, (err)); \
+ __get_user_asm("lwi", __gu_val, (ptr), (err)); \
break; \
case 8: \
- __get_user_asm_dword(__gu_val, __gu_addr, (err)); \
+ __get_user_asm_dword(__gu_val, (ptr), (err)); \
break; \
default: \
BUILD_BUG(); \
break; \
} \
- (x) = (__typeof__(*(__gu_addr)))__gu_val; \
+ (x) = (__force __typeof__(*(ptr)))__gu_val; \
} while (0)

#define __get_user_asm(inst, x, addr, err) \
@@ -170,15 +170,7 @@ do { \
: "r"(addr), "i"(-EFAULT) \
: "cc")

-#define put_user(x, ptr) \
-({ \
- long __e = -EFAULT; \
- __typeof__(*(ptr)) __user *__p = (ptr); \
- if (likely(access_ok(VERIFY_WRITE, __p, sizeof(*__p)))) { \
- __e = __put_user(x, __p); \
- } \
- __e; \
-})
+#define put_user __put_user \

#define __put_user(x, ptr) \
({ \
@@ -189,27 +181,37 @@ do { \

#define __put_user_error(x, ptr, err) \
({ \
- __put_user_err((x), (ptr), err); \
+ __put_user_err((x), (ptr), (err)); \
(void)0; \
})

+#define __put_user_check(x, ptr, err) \
+({ \
+ __typeof__(*(ptr)) __user *__p = (ptr); \
+ might_fault(); \
+ if (access_ok(VERIFY_WRITE, __p, sizeof(*__p))) { \
+ __put_user_err((x), __p, (err)); \
+ } else { \
+ (err) = -EFAULT; \
+ } \
+})
+
#define __put_user_err(x, ptr, err) \
do { \
- __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
- __typeof__(*(__pu_addr)) __pu_val = (x); \
- __chk_user_ptr(__pu_addr); \
- switch (sizeof(*(__pu_addr))) { \
+ __typeof__(*(ptr)) __pu_val = (x); \
+ __chk_user_ptr(ptr); \
+ switch (sizeof(*(ptr))) { \
case 1: \
- __put_user_asm("sbi", __pu_val, __pu_addr, (err)); \
+ __put_user_asm("sbi", __pu_val, (ptr), (err)); \
break; \
case 2: \
- __put_user_asm("shi", __pu_val, __pu_addr, (err)); \
+ __put_user_asm("shi", __pu_val, (ptr), (err)); \
break; \
case 4: \
- __put_user_asm("swi", __pu_val, __pu_addr, (err)); \
+ __put_user_asm("swi", __pu_val, (ptr), (err)); \
break; \
case 8: \
- __put_user_asm_dword(__pu_val, __pu_addr, (err)); \
+ __put_user_asm_dword(__pu_val, (ptr), (err)); \
break; \
default: \
BUILD_BUG(); \
--
2.7.4