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/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
#include <linux/module.h>
#include <asm/uaccess.h>
unsigned long __generic_copy_from_user(void *to, const void __user *from,
unsigned long n)
{
unsigned long tmp, res;
asm volatile ("\n"
" tst.l %0\n"
" jeq 2f\n"
"1: moves.l (%1)+,%3\n"
" move.l %3,(%2)+\n"
" subq.l #1,%0\n"
" jne 1b\n"
"2: btst #1,%5\n"
" jeq 4f\n"
"3: moves.w (%1)+,%3\n"
" move.w %3,(%2)+\n"
"4: btst #0,%5\n"
" jeq 6f\n"
"5: moves.b (%1)+,%3\n"
" move.b %3,(%2)+\n"
"6:\n"
" .section .fixup,\"ax\"\n"
" .even\n"
"10: move.l %0,%3\n"
"7: clr.l (%2)+\n"
" subq.l #1,%3\n"
" jne 7b\n"
" lsl.l #2,%0\n"
" btst #1,%5\n"
" jeq 8f\n"
"30: clr.w (%2)+\n"
" addq.l #2,%0\n"
"8: btst #0,%5\n"
" jeq 6b\n"
"50: clr.b (%2)+\n"
" addq.l #1,%0\n"
" jra 6b\n"
" .previous\n"
"\n"
" .section __ex_table,\"a\"\n"
" .align 4\n"
" .long 1b,10b\n"
" .long 3b,30b\n"
" .long 5b,50b\n"
" .previous"
: "=d" (res), "+a" (from), "+a" (to), "=&r" (tmp)
: "0" (n / 4), "d" (n & 3));
return res;
}
EXPORT_SYMBOL(__generic_copy_from_user);
unsigned long __generic_copy_to_user(void __user *to, const void *from,
unsigned long n)
{
unsigned long tmp, res;
asm volatile ("\n"
" tst.l %0\n"
" jeq 4f\n"
"1: move.l (%1)+,%3\n"
"2: moves.l %3,(%2)+\n"
"3: subq.l #1,%0\n"
" jne 1b\n"
"4: btst #1,%5\n"
" jeq 6f\n"
" move.w (%1)+,%3\n"
"5: moves.w %3,(%2)+\n"
"6: btst #0,%5\n"
" jeq 8f\n"
" move.b (%1)+,%3\n"
"7: moves.b %3,(%2)+\n"
"8:\n"
" .section .fixup,\"ax\"\n"
" .even\n"
"20: lsl.l #2,%0\n"
"50: add.l %5,%0\n"
" jra 8b\n"
" .previous\n"
"\n"
" .section __ex_table,\"a\"\n"
" .align 4\n"
" .long 2b,20b\n"
" .long 3b,20b\n"
" .long 5b,50b\n"
" .long 6b,50b\n"
" .long 7b,50b\n"
" .long 8b,50b\n"
" .previous"
: "=d" (res), "+a" (from), "+a" (to), "=&r" (tmp)
: "0" (n / 4), "d" (n & 3));
return res;
}
EXPORT_SYMBOL(__generic_copy_to_user);
/*
* Copy a null terminated string from userspace.
*/
long strncpy_from_user(char *dst, const char __user *src, long count)
{
long res;
char c;
if (count <= 0)
return count;
asm volatile ("\n"
"1: moves.b (%2)+,%4\n"
" move.b %4,(%1)+\n"
" jeq 2f\n"
" subq.l #1,%3\n"
" jne 1b\n"
"2: sub.l %3,%0\n"
"3:\n"
" .section .fixup,\"ax\"\n"
" .even\n"
"10: move.l %5,%0\n"
" jra 3b\n"
" .previous\n"
"\n"
" .section __ex_table,\"a\"\n"
" .align 4\n"
" .long 1b,10b\n"
" .previous"
: "=d" (res), "+a" (dst), "+a" (src), "+r" (count), "=&d" (c)
: "i" (-EFAULT), "0" (count));
return res;
}
EXPORT_SYMBOL(strncpy_from_user);
/*
* Return the size of a string (including the ending 0)
*
* Return 0 on exception, a value greater than N if too long
*/
long strnlen_user(const char __user *src, long n)
{
char c;
long res;
asm volatile ("\n"
"1: subq.l #1,%1\n"
" jmi 3f\n"
"2: moves.b (%0)+,%2\n"
" tst.b %2\n"
" jne 1b\n"
" jra 4f\n"
"\n"
"3: addq.l #1,%0\n"
"4: sub.l %4,%0\n"
"5:\n"
" .section .fixup,\"ax\"\n"
" .even\n"
"20: sub.l %0,%0\n"
" jra 5b\n"
" .previous\n"
"\n"
" .section __ex_table,\"a\"\n"
" .align 4\n"
" .long 2b,20b\n"
" .previous\n"
: "=&a" (res), "+d" (n), "=&d" (c)
: "0" (src), "r" (src));
return res;
}
EXPORT_SYMBOL(strnlen_user);
/*
* Zero Userspace
*/
unsigned long clear_user(void __user *to, unsigned long n)
{
unsigned long res;
asm volatile ("\n"
" tst.l %0\n"
" jeq 3f\n"
"1: moves.l %2,(%1)+\n"
"2: subq.l #1,%0\n"
" jne 1b\n"
"3: btst #1,%4\n"
" jeq 5f\n"
"4: moves.w %2,(%1)+\n"
"5: btst #0,%4\n"
" jeq 7f\n"
"6: moves.b %2,(%1)\n"
"7:\n"
" .section .fixup,\"ax\"\n"
" .even\n"
"10: lsl.l #2,%0\n"
"40: add.l %4,%0\n"
" jra 7b\n"
" .previous\n"
"\n"
" .section __ex_table,\"a\"\n"
" .align 4\n"
" .long 1b,10b\n"
" .long 2b,10b\n"
" .long 4b,40b\n"
" .long 5b,40b\n"
" .long 6b,40b\n"
" .long 7b,40b\n"
" .previous"
: "=d" (res), "+a" (to)
: "r" (0), "0" (n / 4), "d" (n & 3));
return res;
}
EXPORT_SYMBOL(clear_user);
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