Copied from commit 4b842e4e25b1 ("x86: get rid of small
constant size cases in raw_copy_{to,from}_user()")
Very few call sites where that would be triggered remain, and none
of those is anywhere near hot enough to bother.
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/include/asm/uaccess.h | 41 ------------------------------
1 file changed, 41 deletions(-)
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index 93d33f7e8b53..a4d2569173ac 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -398,26 +398,6 @@ static inline unsigned long raw_copy_from_user(void *to,
const void __user *from, unsigned long n)
{
unsigned long ret;
- if (__builtin_constant_p(n) && (n <= 8)) {
- ret = 1;
-
- switch (n) {
- case 1:
- __get_user_size(*(u8 *)to, from, 1, ret);
- break;
- case 2:
- __get_user_size(*(u16 *)to, from, 2, ret);
- break;
- case 4:
- __get_user_size(*(u32 *)to, from, 4, ret);
- break;
- case 8:
- __get_user_size(*(u64 *)to, from, 8, ret);
- break;
- }
- if (ret == 0)
- return 0;
- }
allow_read_from_user(from, n);
ret = __copy_tofrom_user((__force void __user *)to, from, n);
@@ -428,27 +408,6 @@ static inline unsigned long raw_copy_from_user(void *to,
static inline unsigned long
raw_copy_to_user_allowed(void __user *to, const void *from, unsigned long n)
{
- if (__builtin_constant_p(n) && (n <= 8)) {
- unsigned long ret = 1;
-
- switch (n) {
- case 1:
- __put_user_size_allowed(*(u8 *)from, (u8 __user *)to, 1, ret);
- break;
- case 2:
- __put_user_size_allowed(*(u16 *)from, (u16 __user *)to, 2, ret);
- break;
- case 4:
- __put_user_size_allowed(*(u32 *)from, (u32 __user *)to, 4, ret);
- break;
- case 8:
- __put_user_size_allowed(*(u64 *)from, (u64 __user *)to, 8, ret);
- break;
- }
- if (ret == 0)
- return 0;
- }
-
return __copy_tofrom_user(to, (__force const void __user *)from, n);
}
--
2.25.0
__put_user_size_allowed() is only called from __put_user_size() now.
Merge them together.
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/include/asm/uaccess.h | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index a4d2569173ac..2fb1d95f10d3 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -108,22 +108,18 @@ static inline bool __access_ok(unsigned long addr, unsigned long size)
extern long __put_user_bad(void);
-#define __put_user_size_allowed(x, ptr, size, retval) \
+#define __put_user_size(x, ptr, size, retval) \
do { \
__label__ __pu_failed; \
\
retval = 0; \
+ allow_write_to_user(ptr, size); \
__put_user_size_goto(x, ptr, size, __pu_failed); \
+ prevent_write_to_user(ptr, size); \
break; \
\
__pu_failed: \
retval = -EFAULT; \
-} while (0)
-
-#define __put_user_size(x, ptr, size, retval) \
-do { \
- allow_write_to_user(ptr, size); \
- __put_user_size_allowed(x, ptr, size, retval); \
prevent_write_to_user(ptr, size); \
} while (0)
--
2.25.0
Since commit 17bc43367fc2 ("powerpc/uaccess: Implement
unsafe_copy_to_user() as a simple loop"), raw_copy_to_user_allowed()
is only used by raw_copy_to_user().
Merge raw_copy_to_user_allowed() into raw_copy_to_user().
Signed-off-by: Christophe Leroy <[email protected]>
---
arch/powerpc/include/asm/uaccess.h | 8 +-------
1 file changed, 1 insertion(+), 7 deletions(-)
diff --git a/arch/powerpc/include/asm/uaccess.h b/arch/powerpc/include/asm/uaccess.h
index 2fb1d95f10d3..33b2de642120 100644
--- a/arch/powerpc/include/asm/uaccess.h
+++ b/arch/powerpc/include/asm/uaccess.h
@@ -401,19 +401,13 @@ static inline unsigned long raw_copy_from_user(void *to,
return ret;
}
-static inline unsigned long
-raw_copy_to_user_allowed(void __user *to, const void *from, unsigned long n)
-{
- return __copy_tofrom_user(to, (__force const void __user *)from, n);
-}
-
static inline unsigned long
raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
unsigned long ret;
allow_write_to_user(to, n);
- ret = raw_copy_to_user_allowed(to, from, n);
+ ret = __copy_tofrom_user(to, (__force const void __user *)from, n);
prevent_write_to_user(to, n);
return ret;
}
--
2.25.0
On Tue, 9 Feb 2021 14:02:12 +0000 (UTC), Christophe Leroy wrote:
> Copied from commit 4b842e4e25b1 ("x86: get rid of small
> constant size cases in raw_copy_{to,from}_user()")
>
> Very few call sites where that would be triggered remain, and none
> of those is anywhere near hot enough to bother.
Applied to powerpc/next.
[1/3] powerpc/uaccess: get rid of small constant size cases in raw_copy_{to,from}_user()
https://git.kernel.org/powerpc/c/6b385d1d7c0a346758e35b128815afa25d4709ee
[2/3] powerpc/uaccess: Merge __put_user_size_allowed() into __put_user_size()
https://git.kernel.org/powerpc/c/95d019e0f9225954e33b6efcad315be9d548a4d7
[3/3] powerpc/uaccess: Merge raw_copy_to_user_allowed() into raw_copy_to_user()
https://git.kernel.org/powerpc/c/052f9d206f6c4b5b512b8c201d375f2dd194be35
cheers