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1/*
2 * linux/arch/arm/lib/csumpartialcopyuser.S
3 *
4 * Copyright (C) 1995-1998 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 * 27/03/03 Ian Molton Clean up CONFIG_CPU
11 *
12 */
13#include <linux/linkage.h>
14#include <asm/assembler.h>
15#include <asm/errno.h>
16#include <asm/asm-offsets.h>
17
18 .text
19
20 .macro save_regs
21 stmfd sp!, {r1, r2, r4 - r8, lr}
22 .endm
23
24 .macro load_regs
25 ldmfd sp!, {r1, r2, r4 - r8, pc}
26 .endm
27
28 .macro load1b, reg1
29 ldrusr \reg1, r0, 1
30 .endm
31
32 .macro load2b, reg1, reg2
33 ldrusr \reg1, r0, 1
34 ldrusr \reg2, r0, 1
35 .endm
36
37 .macro load1l, reg1
38 ldrusr \reg1, r0, 4
39 .endm
40
41 .macro load2l, reg1, reg2
42 ldrusr \reg1, r0, 4
43 ldrusr \reg2, r0, 4
44 .endm
45
46 .macro load4l, reg1, reg2, reg3, reg4
47 ldrusr \reg1, r0, 4
48 ldrusr \reg2, r0, 4
49 ldrusr \reg3, r0, 4
50 ldrusr \reg4, r0, 4
51 .endm
52
53/*
54 * unsigned int
55 * csum_partial_copy_from_user(const char *src, char *dst, int len, int sum, int *err_ptr)
56 * r0 = src, r1 = dst, r2 = len, r3 = sum, [sp] = *err_ptr
57 * Returns : r0 = checksum, [[sp, #0], #0] = 0 or -EFAULT
58 */
59
60#define FN_ENTRY ENTRY(csum_partial_copy_from_user)
61#define FN_EXIT ENDPROC(csum_partial_copy_from_user)
62
63#include "csumpartialcopygeneric.S"
64
65/*
66 * FIXME: minor buglet here
67 * We don't return the checksum for the data present in the buffer. To do
68 * so properly, we would have to add in whatever registers were loaded before
69 * the fault, which, with the current asm above is not predictable.
70 */
71 .pushsection .fixup,"ax"
72 .align 4
739001: mov r4, #-EFAULT
74 ldr r5, [sp, #8*4] @ *err_ptr
75 str r4, [r5]
76 ldmia sp, {r1, r2} @ retrieve dst, len
77 add r2, r2, r1
78 mov r0, #0 @ zero the buffer
799002: teq r2, r1
80 strneb r0, [r1], #1
81 bne 9002b
82 load_regs
83 .popsection
1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * linux/arch/arm/lib/csumpartialcopyuser.S
4 *
5 * Copyright (C) 1995-1998 Russell King
6 *
7 * 27/03/03 Ian Molton Clean up CONFIG_CPU
8 */
9#include <linux/linkage.h>
10#include <asm/assembler.h>
11#include <asm/errno.h>
12#include <asm/asm-offsets.h>
13
14 .text
15
16#if defined(CONFIG_CPU_SW_DOMAIN_PAN)
17
18 .macro save_regs
19 mrc p15, 0, ip, c3, c0, 0
20 stmfd sp!, {r1, r2, r4 - r8, ip, lr}
21 uaccess_enable ip
22 .endm
23
24 .macro load_regs
25 ldmfd sp!, {r1, r2, r4 - r8, ip, lr}
26 mcr p15, 0, ip, c3, c0, 0
27 ret lr
28 .endm
29
30#elif defined(CONFIG_CPU_TTBR0_PAN)
31
32 .macro save_regs
33 mrc p15, 0, ip, c2, c0, 2 @ read TTBCR
34 stmfd sp!, {r1, r2, r4 - r8, ip, lr}
35 uaccess_enable ip
36 .endm
37
38 .macro load_regs
39 ldmfd sp!, {r1, r2, r4 - r8, ip, lr}
40 mcr p15, 0, ip, c2, c0, 2 @ restore TTBCR
41 ret lr
42 .endm
43
44#else
45
46 .macro save_regs
47 stmfd sp!, {r1, r2, r4 - r8, lr}
48 .endm
49
50 .macro load_regs
51 ldmfd sp!, {r1, r2, r4 - r8, pc}
52 .endm
53
54#endif
55
56 .macro load1b, reg1
57 ldrusr \reg1, r0, 1
58 .endm
59
60 .macro load2b, reg1, reg2
61 ldrusr \reg1, r0, 1
62 ldrusr \reg2, r0, 1
63 .endm
64
65 .macro load1l, reg1
66 ldrusr \reg1, r0, 4
67 .endm
68
69 .macro load2l, reg1, reg2
70 ldrusr \reg1, r0, 4
71 ldrusr \reg2, r0, 4
72 .endm
73
74 .macro load4l, reg1, reg2, reg3, reg4
75 ldrusr \reg1, r0, 4
76 ldrusr \reg2, r0, 4
77 ldrusr \reg3, r0, 4
78 ldrusr \reg4, r0, 4
79 .endm
80
81/*
82 * unsigned int
83 * csum_partial_copy_from_user(const char *src, char *dst, int len)
84 * r0 = src, r1 = dst, r2 = len
85 * Returns : r0 = checksum or 0
86 */
87
88#define FN_ENTRY ENTRY(csum_partial_copy_from_user)
89#define FN_EXIT ENDPROC(csum_partial_copy_from_user)
90
91#include "csumpartialcopygeneric.S"
92
93/*
94 * We report fault by returning 0 csum - impossible in normal case, since
95 * we start with 0xffffffff for initial sum.
96 */
97 .pushsection .text.fixup,"ax"
98 .align 4
999001: mov r0, #0
100 load_regs
101 .popsection