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/*
* linux/arch/arm/lib/copy_from_user.S
*
* Author: Nicolas Pitre
* Created: Sep 29, 2005
* Copyright: MontaVista Software, Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
/*
* Prototype:
*
* size_t __copy_from_user(void *to, const void *from, size_t n)
*
* Purpose:
*
* copy a block to kernel memory from user memory
*
* Params:
*
* to = kernel memory
* from = user memory
* n = number of bytes to copy
*
* Return value:
*
* Number of bytes NOT copied.
*/
.macro ldr1w ptr reg abort
100: ldrt \reg, [\ptr], #4
.section __ex_table, "a"
.long 100b, \abort
.previous
.endm
.macro ldr4w ptr reg1 reg2 reg3 reg4 abort
ldr1w \ptr, \reg1, \abort
ldr1w \ptr, \reg2, \abort
ldr1w \ptr, \reg3, \abort
ldr1w \ptr, \reg4, \abort
.endm
.macro ldr8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
ldr4w \ptr, \reg1, \reg2, \reg3, \reg4, \abort
ldr4w \ptr, \reg5, \reg6, \reg7, \reg8, \abort
.endm
.macro ldr1b ptr reg cond=al abort
100: ldr\cond\()bt \reg, [\ptr], #1
.section __ex_table, "a"
.long 100b, \abort
.previous
.endm
.macro str1w ptr reg abort
str \reg, [\ptr], #4
.endm
.macro str8w ptr reg1 reg2 reg3 reg4 reg5 reg6 reg7 reg8 abort
stmia \ptr!, {\reg1, \reg2, \reg3, \reg4, \reg5, \reg6, \reg7, \reg8}
.endm
.macro str1b ptr reg cond=al abort
str\cond\()b \reg, [\ptr], #1
.endm
.macro enter reg1 reg2
mov r3, #0
stmdb sp!, {r0, r2, r3, \reg1, \reg2}
.endm
.macro exit reg1 reg2
add sp, sp, #8
ldmfd sp!, {r0, \reg1, \reg2}
.endm
.text
ENTRY(__copy_from_user)
#include "copy_template.S"
ENDPROC(__copy_from_user)
.section .fixup,"ax"
.align 0
copy_abort_preamble
ldmfd sp!, {r1, r2}
sub r3, r0, r1
rsb r1, r3, r2
str r1, [sp]
bl __memzero
ldr r0, [sp], #4
copy_abort_end
.previous
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