提交 0dcb409d 编写于 作者: M Michal Simek

microblaze: uaccess: sync put/get/clear_user macros

Add macro description and resort.
Signed-off-by: NMichal Simek <monstr@monstr.eu>
上级 8b651aa4
......@@ -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))
......
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