linux/arch/sparc64/lib/user_fixup.c

72 lines
1.2 KiB
C

/* user_fixup.c: Fix up user copy faults.
*
* Copyright (C) 2004 David S. Miller <davem@redhat.com>
*/
#include <linux/compiler.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <asm/uaccess.h>
/* Calculating the exact fault address when using
* block loads and stores can be very complicated.
* Instead of trying to be clever and handling all
* of the cases, just fix things up simply here.
*/
unsigned long copy_from_user_fixup(void *to, const void __user *from, unsigned long size)
{
char *dst = to;
const char __user *src = from;
while (size) {
if (__get_user(*dst, src))
break;
dst++;
src++;
size--;
}
if (size)
memset(dst, 0, size);
return size;
}
unsigned long copy_to_user_fixup(void __user *to, const void *from, unsigned long size)
{
char __user *dst = to;
const char *src = from;
while (size) {
if (__put_user(*src, dst))
break;
dst++;
src++;
size--;
}
return size;
}
unsigned long copy_in_user_fixup(void __user *to, void __user *from, unsigned long size)
{
char __user *dst = to;
char __user *src = from;
while (size) {
char tmp;
if (__get_user(tmp, src))
break;
if (__put_user(tmp, dst))
break;
dst++;
src++;
size--;
}
return size;
}