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/*
* 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>
#include <asm/page.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
*/
beqid r7,3f
addik r3,r7,0 /* temp_count = len */
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:
beqid r6,3f
addik r3,r6,0
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
/* Loop unrolling for __copy_tofrom_user */
#define COPY(offset) \
1: lwi r4 , r6, 0x0000 + offset; \
2: lwi r19, r6, 0x0004 + offset; \
3: lwi r20, r6, 0x0008 + offset; \
4: lwi r21, r6, 0x000C + offset; \
5: lwi r22, r6, 0x0010 + offset; \
6: lwi r23, r6, 0x0014 + offset; \
7: lwi r24, r6, 0x0018 + offset; \
8: lwi r25, r6, 0x001C + offset; \
9: swi r4 , r5, 0x0000 + offset; \
10: swi r19, r5, 0x0004 + offset; \
11: swi r20, r5, 0x0008 + offset; \
12: swi r21, r5, 0x000C + offset; \
13: swi r22, r5, 0x0010 + offset; \
14: swi r23, r5, 0x0014 + offset; \
15: swi r24, r5, 0x0018 + offset; \
16: swi r25, r5, 0x001C + offset; \
.section __ex_table,"a"; \
.word 1b, 0f; \
.word 2b, 0f; \
.word 3b, 0f; \
.word 4b, 0f; \
.word 5b, 0f; \
.word 6b, 0f; \
.word 7b, 0f; \
.word 8b, 0f; \
.word 9b, 0f; \
.word 10b, 0f; \
.word 11b, 0f; \
.word 12b, 0f; \
.word 13b, 0f; \
.word 14b, 0f; \
.word 15b, 0f; \
.word 16b, 0f; \
.text
#define COPY_80(offset) \
COPY(0x00 + offset);\
COPY(0x20 + offset);\
COPY(0x40 + offset);\
COPY(0x60 + offset);
/*
* 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, 0f /* zero size is not likely */
or r3, r5, r6 /* find if is any to/from unaligned */
or r3, r3, r7 /* find if count is unaligned */
andi r3, r3, 0x3 /* mask last 3 bits */
bneid r3, bu1 /* if r3 is not zero then byte copying */
or r3, r0, r0
rsubi r3, r7, PAGE_SIZE /* detect PAGE_SIZE */
beqid r3, page;
or r3, r0, r0
w1: lw r4, r6, r3 /* at least one 4 byte copy */
w2: sw r4, r5, r3
addik r7, r7, -4
bneid r7, w1
addik r3, r3, 4
addik r3, r7, 0
rtsd r15, 8
nop
.section __ex_table,"a"
.word w1, 0f;
.word w2, 0f;
.text
.align 4 /* Alignment is important to keep icache happy */
page: /* Create room on stack and save registers for storign values */
addik r1, r1, -32
swi r19, r1, 4
swi r20, r1, 8
swi r21, r1, 12
swi r22, r1, 16
swi r23, r1, 20
swi r24, r1, 24
swi r25, r1, 28
loop: /* r4, r19, r20, r21, r22, r23, r24, r25 are used for storing values */
/* Loop unrolling to get performance boost */
COPY_80(0x000);
COPY_80(0x080);
COPY_80(0x100);
COPY_80(0x180);
/* copy loop */
addik r6, r6, 0x200
addik r7, r7, -0x200
bneid r7, loop
addik r5, r5, 0x200
/* Restore register content */
lwi r19, r1, 4
lwi r20, r1, 8
lwi r21, r1, 12
lwi r22, r1, 16
lwi r23, r1, 20
lwi r24, r1, 24
lwi r25, r1, 28
addik r1, r1, 32
/* return back */
addik r3, r7, 0
rtsd r15, 8
nop
.align 4 /* Alignment is important to keep icache happy */
bu1: lbu r4,r6,r3
bu2: sb r4,r5,r3
addik r7,r7,-1
bneid r7,bu1
addik r3,r3,1 /* delay slot */
0:
addik r3,r7,0
rtsd r15,8
nop
.size __copy_tofrom_user, . - __copy_tofrom_user
.section __ex_table,"a"
.word bu1, 0b;
.word bu2, 0b;
.text
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