summary refs log tree commit diff
diff options
context:
space:
mode:
authorVineet Gupta <vgupta@synopsys.com>2013-01-18 15:12:16 +0530
committerVineet Gupta <vgupta@synopsys.com>2013-02-11 20:00:32 +0530
commit05d88a493746819821733e07bed918a6e09f735b (patch)
tree59f1a8d8e291e62507b3b221240ee9b926e14ce7
parent43697cb0973da144156e7d11ddd035aee226ee30 (diff)
downloadlinux-05d88a493746819821733e07bed918a6e09f735b.tar.gz
asm-generic: uaccess: Allow arches to over-ride __{get,put}_user_fn()
As of now these default to calling the arch provided __copy_{to,from}_user()
routines which being general purpose (w.r.t buffer alignment and lengths)
would lead to alignment checks in generated code (for arches which don't
support unaligned load/stores).

Given that in this case we already know that data involved is "unit"
sized and aligned, using the vanilla copy backend is a bit wasteful.

This change thus allows arches to over-ride the aforementioned routines.

Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
-rw-r--r--include/asm-generic/uaccess.h11
1 files changed, 11 insertions, 0 deletions
diff --git a/include/asm-generic/uaccess.h b/include/asm-generic/uaccess.h
index 5f6ee6138f9a..c184aa8ec8cd 100644
--- a/include/asm-generic/uaccess.h
+++ b/include/asm-generic/uaccess.h
@@ -169,12 +169,18 @@ static inline __must_check long __copy_to_user(void __user *to,
 		-EFAULT;					\
 })
 
+#ifndef __put_user_fn
+
 static inline int __put_user_fn(size_t size, void __user *ptr, void *x)
 {
 	size = __copy_to_user(ptr, x, size);
 	return size ? -EFAULT : size;
 }
 
+#define __put_user_fn(sz, u, k)	__put_user_fn(sz, u, k)
+
+#endif
+
 extern int __put_user_bad(void) __attribute__((noreturn));
 
 #define __get_user(x, ptr)					\
@@ -225,12 +231,17 @@ extern int __put_user_bad(void) __attribute__((noreturn));
 		-EFAULT;					\
 })
 
+#ifndef __get_user_fn
 static inline int __get_user_fn(size_t size, const void __user *ptr, void *x)
 {
 	size = __copy_from_user(x, ptr, size);
 	return size ? -EFAULT : size;
 }
 
+#define __get_user_fn(sz, u, k)	__get_user_fn(sz, u, k)
+
+#endif
+
 extern int __get_user_bad(void) __attribute__((noreturn));
 
 #ifndef __copy_from_user_inatomic