WSL2-Linux-Kernel/arch/arm26/lib/putuser.S

110 строки
2.8 KiB
ArmAsm

/*
* linux/arch/arm26/lib/putuser.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.
*
* __put_user_X
*
* Inputs: r0 contains the address
* r1, r2 contains the value
* Outputs: r0 is the error code
* 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 __put_user_bad is not global.
*/
#include <asm/asm-offsets.h>
#include <asm/thread_info.h>
#include <asm/errno.h>
.global __put_user_1
__put_user_1:
bic r2, sp, #0x1f00
bic r2, r2, #0x00ff
str lr, [sp, #-4]!
ldr r2, [r2, #TI_ADDR_LIMIT]
sub r2, r2, #1
cmp r0, r2
bge __put_user_bad
1: cmp r0, #0x02000000
strlsbt r1, [r0]
strgeb r1, [r0]
mov r0, #0
ldmfd sp!, {pc}^
.global __put_user_2
__put_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 __put_user_bad
2: cmp r0, #0x02000000
strlsbt r1, [r0], #1
strgeb r1, [r0], #1
mov r1, r1, lsr #8
3: strlsbt r1, [r0]
strgeb r1, [r0]
mov r0, #0
ldmfd sp!, {pc}^
.global __put_user_4
__put_user_4:
bic r2, sp, #0x1f00
bic r2, r2, #0x00ff
str lr, [sp, #-4]!
ldr r2, [r2, #TI_ADDR_LIMIT]
sub r2, r2, #4
cmp r0, r2
4: bge __put_user_bad
cmp r0, #0x02000000
strlst r1, [r0]
strge r1, [r0]
mov r0, #0
ldmfd sp!, {pc}^
.global __put_user_8
__put_user_8:
bic ip, sp, #0x1f00
bic ip, ip, #0x00ff
str lr, [sp, #-4]!
ldr ip, [ip, #TI_ADDR_LIMIT]
sub ip, ip, #8
cmp r0, ip
bge __put_user_bad
cmp r0, #0x02000000
5: strlst r1, [r0], #4
6: strlst r2, [r0]
strge r1, [r0], #4
strge r2, [r0]
mov r0, #0
ldmfd sp!, {pc}^
__put_user_bad:
mov r0, #-EFAULT
mov pc, lr
.section __ex_table, "a"
.long 1b, __put_user_bad
.long 2b, __put_user_bad
.long 3b, __put_user_bad
.long 4b, __put_user_bad
.long 5b, __put_user_bad
.long 6b, __put_user_bad
.previous