xref: /OK3568_Linux_fs/kernel/arch/arm/lib/putuser.S (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun/* SPDX-License-Identifier: GPL-2.0-only */
2*4882a593Smuzhiyun/*
3*4882a593Smuzhiyun *  linux/arch/arm/lib/putuser.S
4*4882a593Smuzhiyun *
5*4882a593Smuzhiyun *  Copyright (C) 2001 Russell King
6*4882a593Smuzhiyun *
7*4882a593Smuzhiyun *  Idea from x86 version, (C) Copyright 1998 Linus Torvalds
8*4882a593Smuzhiyun *
9*4882a593Smuzhiyun * These functions have a non-standard call interface to make
10*4882a593Smuzhiyun * them more efficient, especially as they return an error
11*4882a593Smuzhiyun * value in addition to the "real" return value.
12*4882a593Smuzhiyun *
13*4882a593Smuzhiyun * __put_user_X
14*4882a593Smuzhiyun *
15*4882a593Smuzhiyun * Inputs:	r0 contains the address
16*4882a593Smuzhiyun *		r1 contains the address limit, which must be preserved
17*4882a593Smuzhiyun *		r2, r3 contains the value
18*4882a593Smuzhiyun * Outputs:	r0 is the error code
19*4882a593Smuzhiyun *		lr corrupted
20*4882a593Smuzhiyun *
21*4882a593Smuzhiyun * No other registers must be altered.  (see <asm/uaccess.h>
22*4882a593Smuzhiyun * for specific ASM register usage).
23*4882a593Smuzhiyun *
24*4882a593Smuzhiyun * Note that ADDR_LIMIT is either 0 or 0xc0000000
25*4882a593Smuzhiyun * Note also that it is intended that __put_user_bad is not global.
26*4882a593Smuzhiyun */
27*4882a593Smuzhiyun#include <linux/linkage.h>
28*4882a593Smuzhiyun#include <asm/assembler.h>
29*4882a593Smuzhiyun#include <asm/errno.h>
30*4882a593Smuzhiyun#include <asm/domain.h>
31*4882a593Smuzhiyun
32*4882a593SmuzhiyunENTRY(__put_user_1)
33*4882a593Smuzhiyun	check_uaccess r0, 1, r1, ip, __put_user_bad
34*4882a593Smuzhiyun1: TUSER(strb)	r2, [r0]
35*4882a593Smuzhiyun	mov	r0, #0
36*4882a593Smuzhiyun	ret	lr
37*4882a593SmuzhiyunENDPROC(__put_user_1)
38*4882a593Smuzhiyun
39*4882a593SmuzhiyunENTRY(__put_user_2)
40*4882a593Smuzhiyun	check_uaccess r0, 2, r1, ip, __put_user_bad
41*4882a593Smuzhiyun#if __LINUX_ARM_ARCH__ >= 6
42*4882a593Smuzhiyun
43*4882a593Smuzhiyun2: TUSER(strh)	r2, [r0]
44*4882a593Smuzhiyun
45*4882a593Smuzhiyun#else
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun	mov	ip, r2, lsr #8
48*4882a593Smuzhiyun#ifndef __ARMEB__
49*4882a593Smuzhiyun2: TUSER(strb)	r2, [r0], #1
50*4882a593Smuzhiyun3: TUSER(strb)	ip, [r0]
51*4882a593Smuzhiyun#else
52*4882a593Smuzhiyun2: TUSER(strb)	ip, [r0], #1
53*4882a593Smuzhiyun3: TUSER(strb)	r2, [r0]
54*4882a593Smuzhiyun#endif
55*4882a593Smuzhiyun
56*4882a593Smuzhiyun#endif /* __LINUX_ARM_ARCH__ >= 6 */
57*4882a593Smuzhiyun	mov	r0, #0
58*4882a593Smuzhiyun	ret	lr
59*4882a593SmuzhiyunENDPROC(__put_user_2)
60*4882a593Smuzhiyun
61*4882a593SmuzhiyunENTRY(__put_user_4)
62*4882a593Smuzhiyun	check_uaccess r0, 4, r1, ip, __put_user_bad
63*4882a593Smuzhiyun4: TUSER(str)	r2, [r0]
64*4882a593Smuzhiyun	mov	r0, #0
65*4882a593Smuzhiyun	ret	lr
66*4882a593SmuzhiyunENDPROC(__put_user_4)
67*4882a593Smuzhiyun
68*4882a593SmuzhiyunENTRY(__put_user_8)
69*4882a593Smuzhiyun	check_uaccess r0, 8, r1, ip, __put_user_bad
70*4882a593Smuzhiyun#ifdef CONFIG_THUMB2_KERNEL
71*4882a593Smuzhiyun5: TUSER(str)	r2, [r0]
72*4882a593Smuzhiyun6: TUSER(str)	r3, [r0, #4]
73*4882a593Smuzhiyun#else
74*4882a593Smuzhiyun5: TUSER(str)	r2, [r0], #4
75*4882a593Smuzhiyun6: TUSER(str)	r3, [r0]
76*4882a593Smuzhiyun#endif
77*4882a593Smuzhiyun	mov	r0, #0
78*4882a593Smuzhiyun	ret	lr
79*4882a593SmuzhiyunENDPROC(__put_user_8)
80*4882a593Smuzhiyun
81*4882a593Smuzhiyun__put_user_bad:
82*4882a593Smuzhiyun	mov	r0, #-EFAULT
83*4882a593Smuzhiyun	ret	lr
84*4882a593SmuzhiyunENDPROC(__put_user_bad)
85*4882a593Smuzhiyun
86*4882a593Smuzhiyun.pushsection __ex_table, "a"
87*4882a593Smuzhiyun	.long	1b, __put_user_bad
88*4882a593Smuzhiyun	.long	2b, __put_user_bad
89*4882a593Smuzhiyun#if __LINUX_ARM_ARCH__ < 6
90*4882a593Smuzhiyun	.long	3b, __put_user_bad
91*4882a593Smuzhiyun#endif
92*4882a593Smuzhiyun	.long	4b, __put_user_bad
93*4882a593Smuzhiyun	.long	5b, __put_user_bad
94*4882a593Smuzhiyun	.long	6b, __put_user_bad
95*4882a593Smuzhiyun.popsection
96