diff options
| -rw-r--r-- | arch/x86/include/asm/uaccess_64.h | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/arch/x86/include/asm/uaccess_64.h b/arch/x86/include/asm/uaccess_64.h index 84210c479fc..987a2c10fe2 100644 --- a/arch/x86/include/asm/uaccess_64.h +++ b/arch/x86/include/asm/uaccess_64.h @@ -192,14 +192,26 @@ static inline int __copy_from_user_nocache(void *dst, const void __user *src, unsigned size) { might_sleep(); - return __copy_user_nocache(dst, src, size, 1); + /* + * In practice this limit means that large file write()s + * which get chunked to 4K copies get handled via + * non-temporal stores here. Smaller writes get handled + * via regular __copy_from_user(): + */ + if (likely(size >= PAGE_SIZE)) + return __copy_user_nocache(dst, src, size, 1); + else + return __copy_from_user(dst, src, size); } static inline int __copy_from_user_inatomic_nocache(void *dst, const void __user *src, unsigned size) { - return __copy_user_nocache(dst, src, size, 0); + if (likely(size >= PAGE_SIZE)) + return __copy_user_nocache(dst, src, size, 0); + else + return __copy_from_user_inatomic(dst, src, size); } unsigned long |