diff options
| -rw-r--r-- | arch/microblaze/include/asm/uaccess.h | 106 |
1 files changed, 69 insertions, 37 deletions
diff --git a/arch/microblaze/include/asm/uaccess.h b/arch/microblaze/include/asm/uaccess.h index 1e8fa4b..6bb9b8f 100644 --- a/arch/microblaze/include/asm/uaccess.h +++ b/arch/microblaze/include/asm/uaccess.h @@ -191,11 +191,38 @@ extern long strnlen_user(const char *src, long count); #else /* CONFIG_MMU */ -/* - * All the __XXX versions macros/functions below do not perform - * access checking. It is assumed that the necessary checks have been - * already performed before the finction (macro) is called. - */ +/* Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail. */ +static inline unsigned long __must_check __clear_user(void __user *to, + unsigned long n) +{ + /* normal memset with two words to __ex_table */ + __asm__ __volatile__ ( \ + "1: sb r0, %2, r0;" \ + " addik %0, %0, -1;" \ + " bneid %0, 1b;" \ + " addik %2, %2, 1;" \ + "2: " \ + __EX_TABLE_SECTION \ + ".word 1b,2b;" \ + ".previous;" \ + : "=r"(n) \ + : "0"(n), "r"(to) + ); + return n; +} + +static inline unsigned long __must_check clear_user(void __user *to, + unsigned long n) +{ + might_sleep(); + if (unlikely(!access_ok(VERIFY_WRITE, to, n))) + return n; + return __clear_user(to, n); +} + +/* put_user and get_user macros */ + +extern long __user_bad(void); #define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \ ({ \ @@ -231,18 +258,53 @@ extern long strnlen_user(const char *src, long count); __get_user_asm("lw", (ptr), __gu_val, __gu_err); \ break; \ default: \ - __gu_val = 0; __gu_err = -EINVAL; \ + /* __gu_val = 0; __gu_err = -EINVAL;*/ __gu_err = __user_bad();\ } \ x = (__typeof__(*(ptr))) __gu_val; \ __gu_err; \ }) +/** + * get_user: - Get a simple variable from user space. + * @x: Variable to store result. + * @ptr: Source address, in user space. + * + * Context: User context only. This function may sleep. + * + * This macro copies a single simple variable from user space to kernel + * space. It supports simple types like char and int, but not larger + * data types like structures or arrays. + * + * @ptr must have pointer-to-simple-variable type, and the result of + * dereferencing @ptr must be assignable to @x without a cast. + * + * Returns zero on success, or -EFAULT on error. + * On error, the variable @x is set to zero. + */ + #define get_user(x, ptr) \ ({ \ access_ok(VERIFY_READ, (ptr), sizeof(*(ptr))) \ ? __get_user((x), (ptr)) : -EFAULT; \ }) +/** + * put_user: - Write a simple value into user space. + * @x: Value to copy to user space. + * @ptr: Destination address, in user space. + * + * Context: User context only. This function may sleep. + * + * This macro copies a single simple value from kernel space to user + * space. It supports simple types like char and int, but not larger + * data types like structures or arrays. + * + * @ptr must have pointer-to-simple-variable type, and @x must be assignable + * to the result of dereferencing @ptr. + * + * Returns zero on success, or -EFAULT on error. + */ + #define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err) \ ({ \ __asm__ __volatile__ ( \ @@ -299,7 +361,7 @@ extern long strnlen_user(const char *src, long count); __put_user_asm_8((ptr), __gu_val, __gu_err); \ break; \ default: \ - __gu_err = -EINVAL; \ + /*__gu_err = -EINVAL;*/ __gu_err = __user_bad(); \ } \ __gu_err; \ }) @@ -310,36 +372,6 @@ extern long strnlen_user(const char *src, long count); ? __put_user((x), (ptr)) : -EFAULT; \ }) -/* Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail. */ -static inline unsigned long __must_check __clear_user(void __user *to, - unsigned long n) -{ - /* normal memset with two words to __ex_table */ - __asm__ __volatile__ ( \ - "1: sb r0, %2, r0;" \ - " addik %0, %0, -1;" \ - " bneid %0, 1b;" \ - " addik %2, %2, 1;" \ - "2: " \ - __EX_TABLE_SECTION \ - ".word 1b,2b;" \ - ".previous;" \ - : "=r"(n) \ - : "0"(n), "r"(to) - ); - return n; -} - -static inline unsigned long __must_check clear_user(void __user *to, - unsigned long n) -{ - might_sleep(); - if (unlikely(!access_ok(VERIFY_WRITE, to, n))) - return n; - - return __clear_user(to, n); -} - #define __copy_from_user(to, from, n) copy_from_user((to), (from), (n)) #define __copy_from_user_inatomic(to, from, n) \ copy_from_user((to), (from), (n)) |