/* SPDX-License-Identifier: GPL-2.0-only */
/*
* linux/arch/arm/lib/getuser.S
*
* Copyright (C) 2001 Russell King
*
* 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
* r1 contains the address limit, which must be preserved
* Outputs: r0 is the error code
* r2, r3 contains the zero-extended value
* lr corrupted
*
* No other registers must be altered. (see <asm/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 <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/errno.h>
#include <asm/domain.h>
ENTRY(__get_user_1)
check_uaccess r0, 1, r1, r2, __get_user_bad
1: TUSER(ldrb) r2, [r0]
mov r0, #0
ret lr
ENDPROC(__get_user_1)
_ASM_NOKPROBE(__get_user_1)
ENTRY(__get_user_2)
check_uaccess r0, 2, r1, r2, __get_user_bad
#if __LINUX_ARM_ARCH__ >= 6
2: TUSER(ldrh) r2, [r0]
#else
#ifdef CONFIG_CPU_USE_DOMAINS
rb .req ip
2: ldrbt r2, [r0], #1
3: ldrbt rb, [r0], #0
#else
rb .req r0
2: ldrb r2, [r0]
3: ldrb rb, [r0, #1]
#endif
#ifndef __ARMEB__
orr r2, r2, rb, lsl #8
#else
orr r2, rb, r2, lsl #8
#endif
#endif /* __LINUX_ARM_ARCH__ >= 6 */
mov r0, #0
ret lr
ENDPROC(__get_user_2)
_ASM_NOKPROBE(__get_user_2)
ENTRY(__get_user_4)
check_uaccess r0, 4, r1, r2, __get_user_bad
4: TUSER(ldr) r2, [r0]
mov r0, #0
ret lr
ENDPROC(__get_user_4)
_ASM_NOKPROBE(__get_user_4)
ENTRY(__get_user_8)
check_uaccess r0, 8, r1, r2, __get_user_bad8
#ifdef CONFIG_THUMB2_KERNEL
5: TUSER(ldr) r2, [r0]
6: TUSER(ldr) r3, [r0, #4]
#else
5: TUSER(ldr) r2, [r0], #4
6: TUSER(ldr) r3, [r0]
#endif
mov r0, #0
ret lr
ENDPROC(__get_user_8)
_ASM_NOKPROBE(__get_user_8)
#ifdef __ARMEB__
ENTRY(__get_user_32t_8)
check_uaccess r0, 8, r1, r2, __get_user_bad
#ifdef CONFIG_CPU_USE_DOMAINS
add r0, r0, #4
7: ldrt r2, [r0]
#else
7: ldr r2, [r0, #4]
#endif
mov r0, #0
ret lr
ENDPROC(__get_user_32t_8)
_ASM_NOKPROBE(__get_user_32t_8)
ENTRY(__get_user_64t_1)
check_uaccess r0, 1, r1, r2, __get_user_bad8
8: TUSER(ldrb) r3, [r0]
mov r0, #0
ret lr
ENDPROC(__get_user_64t_1)
_ASM_NOKPROBE(__get_user_64t_1)
ENTRY(__get_user_64t_2)
check_uaccess r0, 2, r1, r2, __get_user_bad8
#ifdef CONFIG_CPU_USE_DOMAINS
rb .req ip
9: ldrbt r3, [r0], #1
10: ldrbt rb, [r0], #0
#else
rb .req r0
9: ldrb r3, [r0]
10: ldrb rb, [r0, #1]
#endif
orr r3, rb, r3, lsl #8
mov r0, #0
ret lr
ENDPROC(__get_user_64t_2)
_ASM_NOKPROBE(__get_user_64t_2)
ENTRY(__get_user_64t_4)
check_uaccess r0, 4, r1, r2, __get_user_bad8
11: TUSER(ldr) r3, [r0]
mov r0, #0
ret lr
ENDPROC(__get_user_64t_4)
_ASM_NOKPROBE(__get_user_64t_4)
#endif
__get_user_bad8:
mov r3, #0
__get_user_bad:
mov r2, #0
mov r0, #-EFAULT
ret lr
ENDPROC(__get_user_bad)
ENDPROC(__get_user_bad8)
_ASM_NOKPROBE(__get_user_bad)
_ASM_NOKPROBE(__get_user_bad8)
.pushsection __ex_table, "a"
.long 1b, __get_user_bad
.long 2b, __get_user_bad
#if __LINUX_ARM_ARCH__ < 6
.long 3b, __get_user_bad
#endif
.long 4b, __get_user_bad
.long 5b, __get_user_bad8
.long 6b, __get_user_bad8
#ifdef __ARMEB__
.long 7b, __get_user_bad
.long 8b, __get_user_bad8
.long 9b, __get_user_bad8
.long 10b, __get_user_bad8
.long 11b, __get_user_bad8
#endif
.popsection
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