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1/*
2 * linux/arch/arm/lib/getuser.S
3 *
4 * Copyright (C) 2001 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * Idea from x86 version, (C) Copyright 1998 Linus Torvalds
11 *
12 * These functions have a non-standard call interface to make them more
13 * efficient, especially as they return an error value in addition to
14 * the "real" return value.
15 *
16 * __get_user_X
17 *
18 * Inputs: r0 contains the address
19 * r1 contains the address limit, which must be preserved
20 * Outputs: r0 is the error code
21 * r2 contains the zero-extended value
22 * lr corrupted
23 *
24 * No other registers must be altered. (see <asm/uaccess.h>
25 * for specific ASM register usage).
26 *
27 * Note that ADDR_LIMIT is either 0 or 0xc0000000.
28 * Note also that it is intended that __get_user_bad is not global.
29 */
30#include <linux/linkage.h>
31#include <asm/assembler.h>
32#include <asm/errno.h>
33#include <asm/domain.h>
34
35ENTRY(__get_user_1)
36 check_uaccess r0, 1, r1, r2, __get_user_bad
371: TUSER(ldrb) r2, [r0]
38 mov r0, #0
39 mov pc, lr
40ENDPROC(__get_user_1)
41
42ENTRY(__get_user_2)
43 check_uaccess r0, 2, r1, r2, __get_user_bad
44#ifdef CONFIG_CPU_USE_DOMAINS
45rb .req ip
462: ldrbt r2, [r0], #1
473: ldrbt rb, [r0], #0
48#else
49rb .req r0
502: ldrb r2, [r0]
513: ldrb rb, [r0, #1]
52#endif
53#ifndef __ARMEB__
54 orr r2, r2, rb, lsl #8
55#else
56 orr r2, rb, r2, lsl #8
57#endif
58 mov r0, #0
59 mov pc, lr
60ENDPROC(__get_user_2)
61
62ENTRY(__get_user_4)
63 check_uaccess r0, 4, r1, r2, __get_user_bad
644: TUSER(ldr) r2, [r0]
65 mov r0, #0
66 mov pc, lr
67ENDPROC(__get_user_4)
68
69__get_user_bad:
70 mov r2, #0
71 mov r0, #-EFAULT
72 mov pc, lr
73ENDPROC(__get_user_bad)
74
75.pushsection __ex_table, "a"
76 .long 1b, __get_user_bad
77 .long 2b, __get_user_bad
78 .long 3b, __get_user_bad
79 .long 4b, __get_user_bad
80.popsection
1/*
2 * linux/arch/arm/lib/getuser.S
3 *
4 * Copyright (C) 2001 Russell King
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 *
10 * Idea from x86 version, (C) Copyright 1998 Linus Torvalds
11 *
12 * These functions have a non-standard call interface to make them more
13 * efficient, especially as they return an error value in addition to
14 * the "real" return value.
15 *
16 * __get_user_X
17 *
18 * Inputs: r0 contains the address
19 * r1 contains the address limit, which must be preserved
20 * Outputs: r0 is the error code
21 * r2 contains the zero-extended value
22 * lr corrupted
23 *
24 * No other registers must be altered. (see <asm/uaccess.h>
25 * for specific ASM register usage).
26 *
27 * Note that ADDR_LIMIT is either 0 or 0xc0000000.
28 * Note also that it is intended that __get_user_bad is not global.
29 */
30#include <linux/linkage.h>
31#include <asm/assembler.h>
32#include <asm/errno.h>
33#include <asm/domain.h>
34
35ENTRY(__get_user_1)
36 check_uaccess r0, 1, r1, r2, __get_user_bad
371: TUSER(ldrb) r2, [r0]
38 mov r0, #0
39 mov pc, lr
40ENDPROC(__get_user_1)
41
42ENTRY(__get_user_2)
43 check_uaccess r0, 2, r1, r2, __get_user_bad
44#ifdef CONFIG_CPU_USE_DOMAINS
45rb .req ip
462: ldrbt r2, [r0], #1
473: ldrbt rb, [r0], #0
48#else
49rb .req r0
502: ldrb r2, [r0]
513: ldrb rb, [r0, #1]
52#endif
53#ifndef __ARMEB__
54 orr r2, r2, rb, lsl #8
55#else
56 orr r2, rb, r2, lsl #8
57#endif
58 mov r0, #0
59 mov pc, lr
60ENDPROC(__get_user_2)
61
62ENTRY(__get_user_4)
63 check_uaccess r0, 4, r1, r2, __get_user_bad
644: TUSER(ldr) r2, [r0]
65 mov r0, #0
66 mov pc, lr
67ENDPROC(__get_user_4)
68
69__get_user_bad:
70 mov r2, #0
71 mov r0, #-EFAULT
72 mov pc, lr
73ENDPROC(__get_user_bad)
74
75.pushsection __ex_table, "a"
76 .long 1b, __get_user_bad
77 .long 2b, __get_user_bad
78 .long 3b, __get_user_bad
79 .long 4b, __get_user_bad
80.popsection