mirror of
https://github.com/torvalds/linux.git
synced 2024-11-01 01:31:44 +00:00
ca3865bae5
Word copying is used only for aligned addresses. Here is space for improving to use any better copying technique. Look at memcpy implementation. Signed-off-by: Michal Simek <monstr@monstr.eu>
153 lines
2.8 KiB
ArmAsm
153 lines
2.8 KiB
ArmAsm
/*
|
|
* Copyright (C) 2009 Michal Simek <monstr@monstr.eu>
|
|
* Copyright (C) 2009 PetaLogix
|
|
* Copyright (C) 2007 LynuxWorks, Inc.
|
|
*
|
|
* 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/errno.h>
|
|
#include <linux/linkage.h>
|
|
|
|
/*
|
|
* int __strncpy_user(char *to, char *from, int len);
|
|
*
|
|
* Returns:
|
|
* -EFAULT for an exception
|
|
* len if we hit the buffer limit
|
|
* bytes copied
|
|
*/
|
|
|
|
.text
|
|
.globl __strncpy_user;
|
|
.type __strncpy_user, @function
|
|
.align 4;
|
|
__strncpy_user:
|
|
|
|
/*
|
|
* r5 - to
|
|
* r6 - from
|
|
* r7 - len
|
|
* r3 - temp count
|
|
* r4 - temp val
|
|
*/
|
|
addik r3,r7,0 /* temp_count = len */
|
|
beqi r3,3f
|
|
1:
|
|
lbu r4,r6,r0
|
|
sb r4,r5,r0
|
|
|
|
addik r3,r3,-1
|
|
beqi r3,2f /* break on len */
|
|
|
|
addik r5,r5,1
|
|
bneid r4,1b
|
|
addik r6,r6,1 /* delay slot */
|
|
addik r3,r3,1 /* undo "temp_count--" */
|
|
2:
|
|
rsubk r3,r3,r7 /* temp_count = len - temp_count */
|
|
3:
|
|
rtsd r15,8
|
|
nop
|
|
.size __strncpy_user, . - __strncpy_user
|
|
|
|
.section .fixup, "ax"
|
|
.align 2
|
|
4:
|
|
brid 3b
|
|
addik r3,r0, -EFAULT
|
|
|
|
.section __ex_table, "a"
|
|
.word 1b,4b
|
|
|
|
/*
|
|
* int __strnlen_user(char __user *str, int maxlen);
|
|
*
|
|
* Returns:
|
|
* 0 on error
|
|
* maxlen + 1 if no NUL byte found within maxlen bytes
|
|
* size of the string (including NUL byte)
|
|
*/
|
|
|
|
.text
|
|
.globl __strnlen_user;
|
|
.type __strnlen_user, @function
|
|
.align 4;
|
|
__strnlen_user:
|
|
addik r3,r6,0
|
|
beqi r3,3f
|
|
1:
|
|
lbu r4,r5,r0
|
|
beqid r4,2f /* break on NUL */
|
|
addik r3,r3,-1 /* delay slot */
|
|
|
|
bneid r3,1b
|
|
addik r5,r5,1 /* delay slot */
|
|
|
|
addik r3,r3,-1 /* for break on len */
|
|
2:
|
|
rsubk r3,r3,r6
|
|
3:
|
|
rtsd r15,8
|
|
nop
|
|
.size __strnlen_user, . - __strnlen_user
|
|
|
|
.section .fixup,"ax"
|
|
4:
|
|
brid 3b
|
|
addk r3,r0,r0
|
|
|
|
.section __ex_table,"a"
|
|
.word 1b,4b
|
|
|
|
/*
|
|
* int __copy_tofrom_user(char *to, char *from, int len)
|
|
* Return:
|
|
* 0 on success
|
|
* number of not copied bytes on error
|
|
*/
|
|
.text
|
|
.globl __copy_tofrom_user;
|
|
.type __copy_tofrom_user, @function
|
|
.align 4;
|
|
__copy_tofrom_user:
|
|
/*
|
|
* r5 - to
|
|
* r6 - from
|
|
* r7, r3 - count
|
|
* r4 - tempval
|
|
*/
|
|
beqid r7, 3f /* zero size is not likely */
|
|
andi r3, r7, 0x3 /* filter add count */
|
|
bneid r3, 4f /* if is odd value then byte copying */
|
|
or r3, r5, r6 /* find if is any to/from unaligned */
|
|
andi r3, r3, 0x3 /* mask unaligned */
|
|
bneid r3, 1f /* it is unaligned -> then jump */
|
|
or r3, r0, r0
|
|
|
|
/* at least one 4 byte copy */
|
|
5: lw r4, r6, r3
|
|
6: sw r4, r5, r3
|
|
addik r7, r7, -4
|
|
bneid r7, 5b
|
|
addik r3, r3, 4
|
|
addik r3, r7, 0
|
|
rtsd r15, 8
|
|
nop
|
|
4: or r3, r0, r0
|
|
1: lbu r4,r6,r3
|
|
2: sb r4,r5,r3
|
|
addik r7,r7,-1
|
|
bneid r7,1b
|
|
addik r3,r3,1 /* delay slot */
|
|
3:
|
|
addik r3,r7,0
|
|
rtsd r15,8
|
|
nop
|
|
.size __copy_tofrom_user, . - __copy_tofrom_user
|
|
|
|
.section __ex_table,"a"
|
|
.word 1b,3b,2b,3b,5b,3b,6b,3b
|