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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.
*
* Copyright (C) 2009, Wind River Systems Inc
* Implemented by fredrik.markstrom@gmail.com and ivarholmqvist@gmail.com
*/
#include <linux/export.h>
#include <linux/uaccess.h>
asm(".global __copy_from_user\n"
" .type __copy_from_user, @function\n"
"__copy_from_user:\n"
" movi r2,7\n"
" mov r3,r4\n"
" bge r2,r6,1f\n"
" xor r2,r4,r5\n"
" andi r2,r2,3\n"
" movi r7,3\n"
" beq r2,zero,4f\n"
"1: addi r6,r6,-1\n"
" movi r2,-1\n"
" beq r6,r2,3f\n"
" mov r7,r2\n"
"2: ldbu r2,0(r5)\n"
" addi r6,r6,-1\n"
" addi r5,r5,1\n"
" stb r2,0(r3)\n"
" addi r3,r3,1\n"
" bne r6,r7,2b\n"
"3:\n"
" addi r2,r6,1\n"
" ret\n"
"13:mov r2,r6\n"
" ret\n"
"4: andi r2,r4,1\n"
" cmpeq r2,r2,zero\n"
" beq r2,zero,7f\n"
"5: andi r2,r3,2\n"
" beq r2,zero,6f\n"
"9: ldhu r2,0(r5)\n"
" addi r6,r6,-2\n"
" addi r5,r5,2\n"
" sth r2,0(r3)\n"
" addi r3,r3,2\n"
"6: bge r7,r6,1b\n"
"10:ldw r2,0(r5)\n"
" addi r6,r6,-4\n"
" addi r5,r5,4\n"
" stw r2,0(r3)\n"
" addi r3,r3,4\n"
" br 6b\n"
"7: ldbu r2,0(r5)\n"
" addi r6,r6,-1\n"
" addi r5,r5,1\n"
" addi r3,r4,1\n"
" stb r2,0(r4)\n"
" br 5b\n"
".section __ex_table,\"a\"\n"
".word 2b,3b\n"
".word 9b,13b\n"
".word 10b,13b\n"
".word 7b,13b\n"
".previous\n"
);
EXPORT_SYMBOL(__copy_from_user);
asm(
" .global __copy_to_user\n"
" .type __copy_to_user, @function\n"
"__copy_to_user:\n"
" movi r2,7\n"
" mov r3,r4\n"
" bge r2,r6,1f\n"
" xor r2,r4,r5\n"
" andi r2,r2,3\n"
" movi r7,3\n"
" beq r2,zero,4f\n"
/* Bail if we try to copy zero bytes */
"1: addi r6,r6,-1\n"
" movi r2,-1\n"
" beq r6,r2,3f\n"
/* Copy byte by byte for small copies and if src^dst != 0 */
" mov r7,r2\n"
"2: ldbu r2,0(r5)\n"
" addi r5,r5,1\n"
"9: stb r2,0(r3)\n"
" addi r6,r6,-1\n"
" addi r3,r3,1\n"
" bne r6,r7,2b\n"
"3: addi r2,r6,1\n"
" ret\n"
"13:mov r2,r6\n"
" ret\n"
/* If 'to' is an odd address byte copy */
"4: andi r2,r4,1\n"
" cmpeq r2,r2,zero\n"
" beq r2,zero,7f\n"
/* If 'to' is not divideable by four copy halfwords */
"5: andi r2,r3,2\n"
" beq r2,zero,6f\n"
" ldhu r2,0(r5)\n"
" addi r5,r5,2\n"
"10:sth r2,0(r3)\n"
" addi r6,r6,-2\n"
" addi r3,r3,2\n"
/* Copy words */
"6: bge r7,r6,1b\n"
" ldw r2,0(r5)\n"
" addi r5,r5,4\n"
"11:stw r2,0(r3)\n"
" addi r6,r6,-4\n"
" addi r3,r3,4\n"
" br 6b\n"
/* Copy remaining bytes */
"7: ldbu r2,0(r5)\n"
" addi r5,r5,1\n"
" addi r3,r4,1\n"
"12: stb r2,0(r4)\n"
" addi r6,r6,-1\n"
" br 5b\n"
".section __ex_table,\"a\"\n"
".word 9b,3b\n"
".word 10b,13b\n"
".word 11b,13b\n"
".word 12b,13b\n"
".previous\n");
EXPORT_SYMBOL(__copy_to_user);
long strncpy_from_user(char *__to, const char __user *__from, long __len)
{
int l = strnlen_user(__from, __len);
int is_zt = 1;
if (l > __len) {
is_zt = 0;
l = __len;
}
if (l == 0 || copy_from_user(__to, __from, l))
return -EFAULT;
if (is_zt)
l--;
return l;
}
long strnlen_user(const char __user *s, long n)
{
long i;
for (i = 0; i < n; i++) {
char c;
if (get_user(c, s + i) == -EFAULT)
return 0;
if (c == 0)
return i + 1;
}
return n + 1;
}
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