/*
* Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#ifndef __UM_UACCESS_H
#define __UM_UACCESS_H
/* thread_info has a mm_segment_t in it, so put the definition up here */
typedef struct {
unsigned long seg;
} mm_segment_t;
#include <linux/thread_info.h>
#include <linux/errno.h>
#include <asm/processor.h>
#include <asm/elf.h>
#define VERIFY_READ 0
#define VERIFY_WRITE 1
/*
* The fs value determines whether argument validity checking should be
* performed or not. If get_fs() == USER_DS, checking is performed, with
* get_fs() == KERNEL_DS, checking is bypassed.
*
* For historical reasons, these macros are grossly misnamed.
*/
#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
#define KERNEL_DS MAKE_MM_SEG(0xFFFFFFFF)
#define USER_DS MAKE_MM_SEG(TASK_SIZE)
#define get_ds() (KERNEL_DS)
#define get_fs() (current_thread_info()->addr_limit)
#define set_fs(x) (current_thread_info()->addr_limit = (x))
#define segment_eq(a, b) ((a).seg == (b).seg)
#define __under_task_size(addr, size) \
(((unsigned long) (addr) < TASK_SIZE) && \
(((unsigned long) (addr) + (size)) < TASK_SIZE))
#define __access_ok_vsyscall(type, addr, size) \
((type == VERIFY_READ) && \
((unsigned long) (addr) >= FIXADDR_USER_START) && \
((unsigned long) (addr) + (size) <= FIXADDR_USER_END) && \
((unsigned long) (addr) + (size) >= (unsigned long)(addr)))
#define __addr_range_nowrap(addr, size) \
((unsigned long) (addr) <= ((unsigned long) (addr) + (size)))
#define access_ok(type, addr, size) \
(__addr_range_nowrap(addr, size) && \
(__under_task_size(addr, size) || \
__access_ok_vsyscall(type, addr, size) || \
segment_eq(get_fs(), KERNEL_DS)))
extern int copy_from_user(void *to, const void __user *from, int n);
extern int copy_to_user(void __user *to, const void *from, int n);
/*
* strncpy_from_user: - Copy a NUL terminated string from userspace.
* @dst: Destination address, in kernel space. This buffer must be at
* least @count bytes long.
* @src: Source address, in user space.
* @count: Maximum number of bytes to copy, including the trailing NUL.
*
* Copies a NUL-terminated string from userspace to kernel space.
*
* On success, returns the length of the string (not including the trailing
* NUL).
*
* If access to userspace fails, returns -EFAULT (some data may have been
* copied).
*
* If @count is smaller than the length of the string, copies @count bytes
* and returns @count.
*/
extern int strncpy_from_user(char *dst, const char __user *src, int count);
/*
* __clear_user: - Zero a block of memory in user space, with less checking.
* @to: Destination address, in user space.
* @n: Number of bytes to zero.
*
* Zero a block of memory in user space. Caller must check
* the specified block with access_ok() before calling this function.
*
* Returns number of bytes that could not be cleared.
* On success, this will be zero.
*/
extern int __clear_user(void __user *mem, int len);
/*
* clear_user: - Zero a block of memory in user space.
* @to: Destination address, in user space.
* @n: Number of bytes to zero.
*
* Zero a block of memory in user space.
*
* Returns number of bytes that could not be cleared.
* On success, this will be zero.
*/
extern int clear_user(void __user *mem, int len);
/*
* strlen_user: - Get the size of a string in user space.
* @str: The string to measure.
* @n: The maximum valid length
*
* Get the size of a NUL-terminated string in user space.
*
* Returns the size of the string INCLUDING the terminating NUL.
* On exception, returns 0.
* If the string is too long, returns a value greater than @n.
*/
extern int strnlen_user(const void __user *str, int len);
#define __copy_from_user(to, from, n) copy_from_user(to, from, n)
#define __copy_to_user(to, from, n) copy_to_user(to, from, n)
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user
#define __get_user(x, ptr) \
({ \
const __typeof__(*(ptr)) __user *__private_ptr = (ptr); \
__typeof__(x) __private_val; \
int __private_ret = -EFAULT; \
(x) = (__typeof__(*(__private_ptr)))0; \
if (__copy_from_user((__force void *)&__private_val, (__private_ptr),\
sizeof(*(__private_ptr))) == 0) { \
(x) = (__typeof__(*(__private_ptr))) __private_val; \
__private_ret = 0; \
} \
__private_ret; \
})
#define get_user(x, ptr) \
({ \
const __typeof__((*(ptr))) __user *private_ptr = (ptr); \
(access_ok(VERIFY_READ, private_ptr, sizeof(*private_ptr)) ? \
__get_user(x, private_ptr) : ((x) = (__typeof__(*ptr))0, -EFAULT)); \
})
#define __put_user(x, ptr) \
({ \
__typeof__(*(ptr)) __user *__private_ptr = ptr; \
__typeof__(*(__private_ptr)) __private_val; \
int __private_ret = -EFAULT; \
__private_val = (__typeof__(*(__private_ptr))) (x); \
if (__copy_to_user((__private_ptr), &__private_val, \
sizeof(*(__private_ptr))) == 0) { \
__private_ret = 0; \
} \
__private_ret; \
})
#define put_user(x, ptr) \
({ \
__typeof__(*(ptr)) __user *private_ptr = (ptr); \
(access_ok(VERIFY_WRITE, private_ptr, sizeof(*private_ptr)) ? \
__put_user(x, private_ptr) : -EFAULT); \
})
#define strlen_user(str) strnlen_user(str, ~0U >> 1)
struct exception_table_entry
{
unsigned long insn;
unsigned long fixup;
};
#endif
