diff options
Diffstat (limited to 'arch/x86/include/asm/uaccess_64.h')
| -rw-r--r-- | arch/x86/include/asm/uaccess_64.h | 94 |
1 files changed, 61 insertions, 33 deletions
diff --git a/arch/x86/include/asm/uaccess_64.h b/arch/x86/include/asm/uaccess_64.h index 84210c479fc..12a26b979bf 100644 --- a/arch/x86/include/asm/uaccess_64.h +++ b/arch/x86/include/asm/uaccess_64.h @@ -6,8 +6,9 @@ */ #include <linux/compiler.h> #include <linux/errno.h> -#include <linux/prefetch.h> #include <linux/lockdep.h> +#include <asm/alternative.h> +#include <asm/cpufeature.h> #include <asm/page.h> /* @@ -16,21 +17,42 @@ /* Handles exceptions in both to and from, but doesn't do access_ok */ __must_check unsigned long -copy_user_generic(void *to, const void *from, unsigned len); - +copy_user_enhanced_fast_string(void *to, const void *from, unsigned len); __must_check unsigned long -copy_to_user(void __user *to, const void *from, unsigned len); +copy_user_generic_string(void *to, const void *from, unsigned len); __must_check unsigned long -copy_from_user(void *to, const void __user *from, unsigned len); +copy_user_generic_unrolled(void *to, const void *from, unsigned len); + +static __always_inline __must_check unsigned long +copy_user_generic(void *to, const void *from, unsigned len) +{ + unsigned ret; + + /* + * If CPU has ERMS feature, use copy_user_enhanced_fast_string. + * Otherwise, if CPU has rep_good feature, use copy_user_generic_string. + * Otherwise, use copy_user_generic_unrolled. + */ + alternative_call_2(copy_user_generic_unrolled, + copy_user_generic_string, + X86_FEATURE_REP_GOOD, + copy_user_enhanced_fast_string, + X86_FEATURE_ERMS, + ASM_OUTPUT2("=a" (ret), "=D" (to), "=S" (from), + "=d" (len)), + "1" (to), "2" (from), "3" (len) + : "memory", "rcx", "r8", "r9", "r10", "r11"); + return ret; +} + __must_check unsigned long copy_in_user(void __user *to, const void __user *from, unsigned len); 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; - might_fault(); if (!__builtin_constant_p(size)) return copy_user_generic(dst, (__force void *)src, size); switch (size) { @@ -70,11 +92,17 @@ int __copy_from_user(void *dst, const void __user *src, unsigned size) } 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; - might_fault(); if (!__builtin_constant_p(size)) return copy_user_generic((__force void *)dst, src, size); switch (size) { @@ -88,11 +116,11 @@ int __copy_to_user(void __user *dst, const void *src, unsigned size) ret, "l", "k", "ir", 4); return ret; case 8:__put_user_asm(*(u64 *)src, (u64 __user *)dst, - ret, "q", "", "ir", 8); + ret, "q", "", "er", 8); return ret; case 10: __put_user_asm(*(u64 *)src, (u64 __user *)dst, - ret, "q", "", "ir", 10); + ret, "q", "", "er", 10); if (unlikely(ret)) return ret; asm("":::"memory"); @@ -101,12 +129,12 @@ int __copy_to_user(void __user *dst, const void *src, unsigned size) return ret; case 16: __put_user_asm(*(u64 *)src, (u64 __user *)dst, - ret, "q", "", "ir", 16); + ret, "q", "", "er", 16); if (unlikely(ret)) return ret; asm("":::"memory"); __put_user_asm(1[(u64 *)src], 1 + (u64 __user *)dst, - ret, "q", "", "ir", 8); + ret, "q", "", "er", 8); return ret; default: return copy_user_generic((__force void *)dst, src, size); @@ -114,6 +142,13 @@ 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 int __copy_in_user(void __user *dst, const void __user *src, unsigned size) { int ret = 0; @@ -157,7 +192,7 @@ int __copy_in_user(void __user *dst, const void __user *src, unsigned size) ret, "q", "", "=r", 8); if (likely(!ret)) __put_user_asm(tmp, (u64 __user *)dst, - ret, "q", "", "ir", 8); + ret, "q", "", "er", 8); return ret; } default: @@ -166,38 +201,31 @@ int __copy_in_user(void __user *dst, const void __user *src, unsigned size) } } -__must_check long -strncpy_from_user(char *dst, const char __user *src, long count); -__must_check long -__strncpy_from_user(char *dst, const char __user *src, long count); -__must_check long strnlen_user(const char __user *str, long n); -__must_check long __strnlen_user(const char __user *str, long n); -__must_check long strlen_user(const char __user *str); -__must_check unsigned long clear_user(void __user *mem, unsigned long len); -__must_check unsigned long __clear_user(void __user *mem, unsigned long len); - -__must_check long __copy_from_user_inatomic(void *dst, const void __user *src, - unsigned size); +static __must_check __always_inline int +__copy_from_user_inatomic(void *dst, const void __user *src, unsigned size) +{ + return __copy_from_user_nocheck(dst, src, size); +} static __must_check __always_inline int __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(dst, src, size); } extern long __copy_user_nocache(void *dst, const void __user *src, unsigned size, int zerorest); -static inline int __copy_from_user_nocache(void *dst, const void __user *src, - unsigned size) +static inline int +__copy_from_user_nocache(void *dst, const void __user *src, unsigned size) { - might_sleep(); + might_fault(); return __copy_user_nocache(dst, src, size, 1); } -static inline int __copy_from_user_inatomic_nocache(void *dst, - const void __user *src, - unsigned 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); } |