1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
3
4 #include <linux/uaccess.h>
5 #include <linux/types.h>
6
raw_copy_from_user(void * to,const void * from,unsigned long n)7 unsigned long raw_copy_from_user(void *to, const void *from,
8 unsigned long n)
9 {
10 int tmp, nsave;
11
12 __asm__ __volatile__(
13 "0: cmpnei %1, 0 \n"
14 " bf 7f \n"
15 " mov %3, %1 \n"
16 " or %3, %2 \n"
17 " andi %3, 3 \n"
18 " cmpnei %3, 0 \n"
19 " bf 1f \n"
20 " br 5f \n"
21 "1: cmplti %0, 16 \n"
22 " bt 3f \n"
23 "2: ldw %3, (%2, 0) \n"
24 "10: ldw %4, (%2, 4) \n"
25 " stw %3, (%1, 0) \n"
26 " stw %4, (%1, 4) \n"
27 "11: ldw %3, (%2, 8) \n"
28 "12: ldw %4, (%2, 12) \n"
29 " stw %3, (%1, 8) \n"
30 " stw %4, (%1, 12) \n"
31 " addi %2, 16 \n"
32 " addi %1, 16 \n"
33 " subi %0, 16 \n"
34 " br 1b \n"
35 "3: cmplti %0, 4 \n"
36 " bt 5f \n"
37 "4: ldw %3, (%2, 0) \n"
38 " stw %3, (%1, 0) \n"
39 " addi %2, 4 \n"
40 " addi %1, 4 \n"
41 " subi %0, 4 \n"
42 " br 3b \n"
43 "5: cmpnei %0, 0 \n"
44 " bf 7f \n"
45 "6: ldb %3, (%2, 0) \n"
46 " stb %3, (%1, 0) \n"
47 " addi %2, 1 \n"
48 " addi %1, 1 \n"
49 " subi %0, 1 \n"
50 " br 5b \n"
51 "8: stw %3, (%1, 0) \n"
52 " subi %0, 4 \n"
53 " bf 7f \n"
54 "9: subi %0, 8 \n"
55 " bf 7f \n"
56 "13: stw %3, (%1, 8) \n"
57 " subi %0, 12 \n"
58 " bf 7f \n"
59 ".section __ex_table, \"a\" \n"
60 ".align 2 \n"
61 ".long 2b, 7f \n"
62 ".long 4b, 7f \n"
63 ".long 6b, 7f \n"
64 ".long 10b, 8b \n"
65 ".long 11b, 9b \n"
66 ".long 12b,13b \n"
67 ".previous \n"
68 "7: \n"
69 : "=r"(n), "=r"(to), "=r"(from), "=r"(nsave),
70 "=r"(tmp)
71 : "0"(n), "1"(to), "2"(from)
72 : "memory");
73
74 return n;
75 }
76 EXPORT_SYMBOL(raw_copy_from_user);
77
raw_copy_to_user(void * to,const void * from,unsigned long n)78 unsigned long raw_copy_to_user(void *to, const void *from,
79 unsigned long n)
80 {
81 int w0, w1, w2, w3;
82
83 __asm__ __volatile__(
84 "0: cmpnei %1, 0 \n"
85 " bf 8f \n"
86 " mov %3, %1 \n"
87 " or %3, %2 \n"
88 " andi %3, 3 \n"
89 " cmpnei %3, 0 \n"
90 " bf 1f \n"
91 " br 5f \n"
92 "1: cmplti %0, 16 \n" /* 4W */
93 " bt 3f \n"
94 " ldw %3, (%2, 0) \n"
95 " ldw %4, (%2, 4) \n"
96 " ldw %5, (%2, 8) \n"
97 " ldw %6, (%2, 12) \n"
98 "2: stw %3, (%1, 0) \n"
99 "9: stw %4, (%1, 4) \n"
100 "10: stw %5, (%1, 8) \n"
101 "11: stw %6, (%1, 12) \n"
102 " addi %2, 16 \n"
103 " addi %1, 16 \n"
104 " subi %0, 16 \n"
105 " br 1b \n"
106 "3: cmplti %0, 4 \n" /* 1W */
107 " bt 5f \n"
108 " ldw %3, (%2, 0) \n"
109 "4: stw %3, (%1, 0) \n"
110 " addi %2, 4 \n"
111 " addi %1, 4 \n"
112 " subi %0, 4 \n"
113 " br 3b \n"
114 "5: cmpnei %0, 0 \n" /* 1B */
115 " bf 13f \n"
116 " ldb %3, (%2, 0) \n"
117 "6: stb %3, (%1, 0) \n"
118 " addi %2, 1 \n"
119 " addi %1, 1 \n"
120 " subi %0, 1 \n"
121 " br 5b \n"
122 "7: subi %0, 4 \n"
123 "8: subi %0, 4 \n"
124 "12: subi %0, 4 \n"
125 " br 13f \n"
126 ".section __ex_table, \"a\" \n"
127 ".align 2 \n"
128 ".long 2b, 13f \n"
129 ".long 4b, 13f \n"
130 ".long 6b, 13f \n"
131 ".long 9b, 12b \n"
132 ".long 10b, 8b \n"
133 ".long 11b, 7b \n"
134 ".previous \n"
135 "13: \n"
136 : "=r"(n), "=r"(to), "=r"(from), "=r"(w0),
137 "=r"(w1), "=r"(w2), "=r"(w3)
138 : "0"(n), "1"(to), "2"(from)
139 : "memory");
140
141 return n;
142 }
143 EXPORT_SYMBOL(raw_copy_to_user);
144
145 /*
146 * __clear_user: - Zero a block of memory in user space, with less checking.
147 * @to: Destination address, in user space.
148 * @n: Number of bytes to zero.
149 *
150 * Zero a block of memory in user space. Caller must check
151 * the specified block with access_ok() before calling this function.
152 *
153 * Returns number of bytes that could not be cleared.
154 * On success, this will be zero.
155 */
156 unsigned long
__clear_user(void __user * to,unsigned long n)157 __clear_user(void __user *to, unsigned long n)
158 {
159 int data, value, tmp;
160
161 __asm__ __volatile__(
162 "0: cmpnei %1, 0 \n"
163 " bf 7f \n"
164 " mov %3, %1 \n"
165 " andi %3, 3 \n"
166 " cmpnei %3, 0 \n"
167 " bf 1f \n"
168 " br 5f \n"
169 "1: cmplti %0, 32 \n" /* 4W */
170 " bt 3f \n"
171 "8: stw %2, (%1, 0) \n"
172 "10: stw %2, (%1, 4) \n"
173 "11: stw %2, (%1, 8) \n"
174 "12: stw %2, (%1, 12) \n"
175 "13: stw %2, (%1, 16) \n"
176 "14: stw %2, (%1, 20) \n"
177 "15: stw %2, (%1, 24) \n"
178 "16: stw %2, (%1, 28) \n"
179 " addi %1, 32 \n"
180 " subi %0, 32 \n"
181 " br 1b \n"
182 "3: cmplti %0, 4 \n" /* 1W */
183 " bt 5f \n"
184 "4: stw %2, (%1, 0) \n"
185 " addi %1, 4 \n"
186 " subi %0, 4 \n"
187 " br 3b \n"
188 "5: cmpnei %0, 0 \n" /* 1B */
189 "9: bf 7f \n"
190 "6: stb %2, (%1, 0) \n"
191 " addi %1, 1 \n"
192 " subi %0, 1 \n"
193 " br 5b \n"
194 ".section __ex_table,\"a\" \n"
195 ".align 2 \n"
196 ".long 8b, 9b \n"
197 ".long 10b, 9b \n"
198 ".long 11b, 9b \n"
199 ".long 12b, 9b \n"
200 ".long 13b, 9b \n"
201 ".long 14b, 9b \n"
202 ".long 15b, 9b \n"
203 ".long 16b, 9b \n"
204 ".long 4b, 9b \n"
205 ".long 6b, 9b \n"
206 ".previous \n"
207 "7: \n"
208 : "=r"(n), "=r" (data), "=r"(value), "=r"(tmp)
209 : "0"(n), "1"(to), "2"(0)
210 : "memory");
211
212 return n;
213 }
214 EXPORT_SYMBOL(__clear_user);
215