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Merge branch 'x86-uaccess-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

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Pull x86 uaccess changes from Ingo Molnar:
 "A single change that micro-optimizes __copy_*_user_inatomic(), used by
  the futex code"

* 'x86-uaccess-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86: Add 1/2/4/8 byte optimization to 64bit __copy_{from,to}_user_inatomic
This commit is contained in:
Linus Torvalds
2013-11-12 11:46:06 +09:00
parent 986189f9ec ff47ab4ff3
commit c2136301e4
1 changed files with 18 additions and 6 deletions
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24
arch/x86/include/asm/uaccess_64.h
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@@ -49,11 +49,10 @@ __must_check unsigned long
copy_in_user(void __user *to, const void __user *from, unsigned len); copy_in_user(void __user *to, const void __user *from, unsigned len);
static __always_inline __must_check static __always_inline __must_check
int __copy_from_user(void *dst, const void __user *src, unsigned size) int __copy_from_user_nocheck(void *dst, const void __user *src, unsigned size)
{ {
int ret = 0; int ret = 0;
might_fault();
if (!__builtin_constant_p(size)) if (!__builtin_constant_p(size))
return copy_user_generic(dst, (__force void *)src, size); return copy_user_generic(dst, (__force void *)src, size);
switch (size) { switch (size) {
@@ -93,11 +92,17 @@ int __copy_from_user(void *dst, const void __user *src, unsigned size)
} }
static __always_inline __must_check static __always_inline __must_check
int __copy_to_user(void __user *dst, const void *src, unsigned size) int __copy_from_user(void *dst, const void __user *src, unsigned size)
{
might_fault();
return __copy_from_user_nocheck(dst, src, size);
}
static __always_inline __must_check
int __copy_to_user_nocheck(void __user *dst, const void *src, unsigned size)
{ {
int ret = 0; int ret = 0;
might_fault();
if (!__builtin_constant_p(size)) if (!__builtin_constant_p(size))
return copy_user_generic((__force void *)dst, src, size); return copy_user_generic((__force void *)dst, src, size);
switch (size) { switch (size) {
@@ -136,6 +141,13 @@ int __copy_to_user(void __user *dst, const void *src, unsigned size)
} }
} }
static __always_inline __must_check
int __copy_to_user(void __user *dst, const void *src, unsigned size)
{
might_fault();
return __copy_to_user_nocheck(dst, src, size);
}
static __always_inline __must_check static __always_inline __must_check
int __copy_in_user(void __user *dst, const void __user *src, unsigned size) int __copy_in_user(void __user *dst, const void __user *src, unsigned size)
{ {
@@ -192,13 +204,13 @@ int __copy_in_user(void __user *dst, const void __user *src, unsigned size)
static __must_check __always_inline int static __must_check __always_inline int
__copy_from_user_inatomic(void *dst, const void __user *src, unsigned size) __copy_from_user_inatomic(void *dst, const void __user *src, unsigned size)
{ {
return copy_user_generic(dst, (__force const void *)src, size); return __copy_from_user_nocheck(dst, (__force const void *)src, size);
} }
static __must_check __always_inline int static __must_check __always_inline int
__copy_to_user_inatomic(void __user *dst, const void *src, unsigned size) __copy_to_user_inatomic(void __user *dst, const void *src, unsigned size)
{ {
return copy_user_generic((__force void *)dst, src, size); return __copy_to_user_nocheck((__force void *)dst, src, size);
} }
extern long __copy_user_nocache(void *dst, const void __user *src, extern long __copy_user_nocache(void *dst, const void __user *src,