/*
* linux/arch/arm26/lib/getuser.S
*
* Copyright (C) 2001 Russell King
*
* 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.
*
* Idea from x86 version, (C) Copyright 1998 Linus Torvalds
*
* These functions have a non-standard call interface to make them more
* efficient, especially as they return an error value in addition to
* the "real" return value.
*
* __get_user_X
*
* Inputs: r0 contains the address
* Outputs: r0 is the error code
* r1, r2 contains the zero-extended value
* lr corrupted
*
* No other registers must be altered. (see include/asm-arm/uaccess.h
* for specific ASM register usage).
*
* Note that ADDR_LIMIT is either 0 or 0xc0000000.
* Note also that it is intended that __get_user_bad is not global.
*/
#include <asm/asm-offsets.h>
#include <asm/thread_info.h>
#include <asm/errno.h>
.global __get_user_1
__get_user_1:
bic r1, sp, #0x1f00
bic r1, r1, #0x00ff
str lr, [sp, #-4]!
ldr r1, [r1, #TI_ADDR_LIMIT]
sub r1, r1, #1
cmp r0, r1
bge __get_user_bad
cmp r0, #0x02000000
1: ldrlsbt r1, [r0]
ldrgeb r1, [r0]
mov r0, #0
ldmfd sp!, {pc}^
.global __get_user_2
__get_user_2:
bic r2, sp, #0x1f00
bic r2, r2, #0x00ff
str lr, [sp, #-4]!
ldr r2, [r2, #TI_ADDR_LIMIT]
sub r2, r2, #2
cmp r0, r2
bge __get_user_bad
cmp r0, #0x02000000
2: ldrlsbt r1, [r0], #1
3: ldrlsbt r2, [r0]
ldrgeb r1, [r0], #1
ldrgeb r2, [r0]
orr r1, r1, r2, lsl #8
mov r0, #0
ldmfd sp!, {pc}^
.global __get_user_4
__get_user_4:
bic r1, sp, #0x1f00
bic r1, r1, #0x00ff
str lr, [sp, #-4]!
ldr r1, [r1, #TI_ADDR_LIMIT]
sub r1, r1, #4
cmp r0, r1
bge __get_user_bad
cmp r0, #0x02000000
4: ldrlst r1, [r0]
ldrge r1, [r0]
mov r0, #0
ldmfd sp!, {pc}^
.global __get_user_8
__get_user_8:
bic r2, sp, #0x1f00
bic r2, r2, #0x00ff
str lr, [sp, #-4]!
ldr r2, [r2, #TI_ADDR_LIMIT]
sub r2, r2, #8
cmp r0, r2
bge __get_user_bad_8
cmp r0, #0x02000000
5: ldrlst r1, [r0], #4
6: ldrlst r2, [r0]
ldrge r1, [r0], #4
ldrge r2, [r0]
mov r0, #0
ldmfd sp!, {pc}^
__get_user_bad_8:
mov r2, #0
__get_user_bad:
mov r1, #0
mov r0, #-EFAULT
ldmfd sp!, {pc}^
.section __ex_table, "a"
.long 1b, __get_user_bad
.long 2b, __get_user_bad
.long 3b, __get_user_bad
.long 4b, __get_user_bad
.long 5b, __get_user_bad_8
.long 6b, __get_user_bad_8
.previous
