/*
* Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
#ifndef __ARCH_UM_UACCESS_H
#define __ARCH_UM_UACCESS_H
#include <asm/elf.h>
#include <asm/fixmap.h>
#include "sysdep/archsetjmp.h"
#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);
extern int __do_copy_to_user(void *to, const void *from, int n,
void **fault_addr, jmp_buf **fault_catcher);
extern void __do_copy(void *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);
#endif
