tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'x86-uaccess-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
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
+18
-6
+18
-6
arch/x86/include/asm/uaccess_64.h
+18
-6
arch/x86/include/asm/uaccess_64.h
···
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copy_in_user(void __user *to, const void __user *from, unsigned len);
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static __always_inline __must_check
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-
int __copy_from_user(void *dst, const void __user *src, unsigned size)
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+
int __copy_from_user_nocheck(void *dst, const void __user *src, unsigned size)
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{
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int ret = 0;
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-
might_fault();
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if (!__builtin_constant_p(size))
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return copy_user_generic(dst, (__force void *)src, size);
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switch (size) {
···
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}
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static __always_inline __must_check
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-
int __copy_to_user(void __user *dst, const void *src, unsigned size)
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+
int __copy_from_user(void *dst, const void __user *src, unsigned size)
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+
{
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+
might_fault();
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return __copy_from_user_nocheck(dst, src, size);
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+
}
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+
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+
static __always_inline __must_check
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+
int __copy_to_user_nocheck(void __user *dst, const void *src, unsigned size)
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{
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int ret = 0;
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-
might_fault();
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if (!__builtin_constant_p(size))
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return copy_user_generic((__force void *)dst, src, size);
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switch (size) {
···
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default:
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return copy_user_generic((__force void *)dst, src, size);
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}
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+
}
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+
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static __always_inline __must_check
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+
int __copy_to_user(void __user *dst, const void *src, unsigned size)
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+
{
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might_fault();
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return __copy_to_user_nocheck(dst, src, size);
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}
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static __always_inline __must_check
···
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static __must_check __always_inline int
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__copy_from_user_inatomic(void *dst, const void __user *src, unsigned size)
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{
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-
return copy_user_generic(dst, (__force const void *)src, size);
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+
return __copy_from_user_nocheck(dst, (__force const void *)src, size);
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}
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static __must_check __always_inline int
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__copy_to_user_inatomic(void __user *dst, const void *src, unsigned size)
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{
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-
return copy_user_generic((__force void *)dst, src, size);
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return __copy_to_user_nocheck((__force void *)dst, src, size);
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}
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extern long __copy_user_nocache(void *dst, const void __user *src,