uaccess.c
2.87 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file COPYING in the main directory of this archive
* for more details.
*/
#include <linux/module.h>
#include <asm/uaccess.h>
unsigned long __generic_copy_from_user(void *to, const void __user *from,
unsigned long n)
{
unsigned long tmp, res;
asm volatile ("\n"
" tst.l %0\n"
" jeq 2f\n"
"1: "MOVES".l (%1)+,%3\n"
" move.l %3,(%2)+\n"
" subq.l #1,%0\n"
" jne 1b\n"
"2: btst #1,%5\n"
" jeq 4f\n"
"3: "MOVES".w (%1)+,%3\n"
" move.w %3,(%2)+\n"
"4: btst #0,%5\n"
" jeq 6f\n"
"5: "MOVES".b (%1)+,%3\n"
" move.b %3,(%2)+\n"
"6:\n"
" .section .fixup,\"ax\"\n"
" .even\n"
"10: move.l %0,%3\n"
"7: clr.l (%2)+\n"
" subq.l #1,%3\n"
" jne 7b\n"
" lsl.l #2,%0\n"
" btst #1,%5\n"
" jeq 8f\n"
"30: clr.w (%2)+\n"
" addq.l #2,%0\n"
"8: btst #0,%5\n"
" jeq 6b\n"
"50: clr.b (%2)+\n"
" addq.l #1,%0\n"
" jra 6b\n"
" .previous\n"
"\n"
" .section __ex_table,\"a\"\n"
" .align 4\n"
" .long 1b,10b\n"
" .long 3b,30b\n"
" .long 5b,50b\n"
" .previous"
: "=d" (res), "+a" (from), "+a" (to), "=&d" (tmp)
: "0" (n / 4), "d" (n & 3));
return res;
}
EXPORT_SYMBOL(__generic_copy_from_user);
unsigned long __generic_copy_to_user(void __user *to, const void *from,
unsigned long n)
{
unsigned long tmp, res;
asm volatile ("\n"
" tst.l %0\n"
" jeq 4f\n"
"1: move.l (%1)+,%3\n"
"2: "MOVES".l %3,(%2)+\n"
"3: subq.l #1,%0\n"
" jne 1b\n"
"4: btst #1,%5\n"
" jeq 6f\n"
" move.w (%1)+,%3\n"
"5: "MOVES".w %3,(%2)+\n"
"6: btst #0,%5\n"
" jeq 8f\n"
" move.b (%1)+,%3\n"
"7: "MOVES".b %3,(%2)+\n"
"8:\n"
" .section .fixup,\"ax\"\n"
" .even\n"
"20: lsl.l #2,%0\n"
"50: add.l %5,%0\n"
" jra 8b\n"
" .previous\n"
"\n"
" .section __ex_table,\"a\"\n"
" .align 4\n"
" .long 2b,20b\n"
" .long 3b,20b\n"
" .long 5b,50b\n"
" .long 6b,50b\n"
" .long 7b,50b\n"
" .long 8b,50b\n"
" .previous"
: "=d" (res), "+a" (from), "+a" (to), "=&d" (tmp)
: "0" (n / 4), "d" (n & 3));
return res;
}
EXPORT_SYMBOL(__generic_copy_to_user);
/*
* Zero Userspace
*/
unsigned long __clear_user(void __user *to, unsigned long n)
{
unsigned long res;
asm volatile ("\n"
" tst.l %0\n"
" jeq 3f\n"
"1: "MOVES".l %2,(%1)+\n"
"2: subq.l #1,%0\n"
" jne 1b\n"
"3: btst #1,%4\n"
" jeq 5f\n"
"4: "MOVES".w %2,(%1)+\n"
"5: btst #0,%4\n"
" jeq 7f\n"
"6: "MOVES".b %2,(%1)\n"
"7:\n"
" .section .fixup,\"ax\"\n"
" .even\n"
"10: lsl.l #2,%0\n"
"40: add.l %4,%0\n"
" jra 7b\n"
" .previous\n"
"\n"
" .section __ex_table,\"a\"\n"
" .align 4\n"
" .long 1b,10b\n"
" .long 2b,10b\n"
" .long 4b,40b\n"
" .long 5b,40b\n"
" .long 6b,40b\n"
" .long 7b,40b\n"
" .previous"
: "=d" (res), "+a" (to)
: "d" (0), "0" (n / 4), "d" (n & 3));
return res;
}
EXPORT_SYMBOL(__clear_user);