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1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * OpenRISC Linux
4 *
5 * Linux architectural port borrowing liberally from similar works of
6 * others. All original copyrights apply as per the original source
7 * declaration.
8 *
9 * OpenRISC implementation:
10 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
11 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
12 * et al.
13 */
14
15#ifndef __ASM_OPENRISC_UACCESS_H
16#define __ASM_OPENRISC_UACCESS_H
17
18/*
19 * User space memory access functions
20 */
21#include <linux/prefetch.h>
22#include <linux/string.h>
23#include <asm/page.h>
24#include <asm/extable.h>
25#include <asm-generic/access_ok.h>
26
27/*
28 * These are the main single-value transfer routines. They automatically
29 * use the right size if we just have the right pointer type.
30 *
31 * This gets kind of ugly. We want to return _two_ values in "get_user()"
32 * and yet we don't want to do any pointers, because that is too much
33 * of a performance impact. Thus we have a few rather ugly macros here,
34 * and hide all the uglyness from the user.
35 *
36 * The "__xxx" versions of the user access functions are versions that
37 * do not verify the address space, that must have been done previously
38 * with a separate "access_ok()" call (this is used when we do multiple
39 * accesses to the same area of user memory).
40 *
41 * As we use the same address space for kernel and user data on the
42 * PowerPC, we can just do these as direct assignments. (Of course, the
43 * exception handling means that it's no longer "just"...)
44 */
45#define get_user(x, ptr) \
46 __get_user_check((x), (ptr), sizeof(*(ptr)))
47#define put_user(x, ptr) \
48 __put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
49
50#define __get_user(x, ptr) \
51 __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
52#define __put_user(x, ptr) \
53 __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
54
55extern long __put_user_bad(void);
56
57#define __put_user_nocheck(x, ptr, size) \
58({ \
59 long __pu_err; \
60 __put_user_size((x), (ptr), (size), __pu_err); \
61 __pu_err; \
62})
63
64#define __put_user_check(x, ptr, size) \
65({ \
66 long __pu_err = -EFAULT; \
67 __typeof__(*(ptr)) __user *__pu_addr = (ptr); \
68 if (access_ok(__pu_addr, size)) \
69 __put_user_size((x), __pu_addr, (size), __pu_err); \
70 __pu_err; \
71})
72
73#define __put_user_size(x, ptr, size, retval) \
74do { \
75 retval = 0; \
76 switch (size) { \
77 case 1: __put_user_asm(x, ptr, retval, "l.sb"); break; \
78 case 2: __put_user_asm(x, ptr, retval, "l.sh"); break; \
79 case 4: __put_user_asm(x, ptr, retval, "l.sw"); break; \
80 case 8: __put_user_asm2(x, ptr, retval); break; \
81 default: __put_user_bad(); \
82 } \
83} while (0)
84
85struct __large_struct {
86 unsigned long buf[100];
87};
88#define __m(x) (*(struct __large_struct *)(x))
89
90/*
91 * We don't tell gcc that we are accessing memory, but this is OK
92 * because we do not write to any memory gcc knows about, so there
93 * are no aliasing issues.
94 */
95#define __put_user_asm(x, addr, err, op) \
96 __asm__ __volatile__( \
97 "1: "op" 0(%2),%1\n" \
98 "2:\n" \
99 ".section .fixup,\"ax\"\n" \
100 "3: l.addi %0,r0,%3\n" \
101 " l.j 2b\n" \
102 " l.nop\n" \
103 ".previous\n" \
104 ".section __ex_table,\"a\"\n" \
105 " .align 2\n" \
106 " .long 1b,3b\n" \
107 ".previous" \
108 : "=r"(err) \
109 : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err))
110
111#define __put_user_asm2(x, addr, err) \
112 __asm__ __volatile__( \
113 "1: l.sw 0(%2),%1\n" \
114 "2: l.sw 4(%2),%H1\n" \
115 "3:\n" \
116 ".section .fixup,\"ax\"\n" \
117 "4: l.addi %0,r0,%3\n" \
118 " l.j 3b\n" \
119 " l.nop\n" \
120 ".previous\n" \
121 ".section __ex_table,\"a\"\n" \
122 " .align 2\n" \
123 " .long 1b,4b\n" \
124 " .long 2b,4b\n" \
125 ".previous" \
126 : "=r"(err) \
127 : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err))
128
129#define __get_user_nocheck(x, ptr, size) \
130({ \
131 long __gu_err; \
132 __get_user_size((x), (ptr), (size), __gu_err); \
133 __gu_err; \
134})
135
136#define __get_user_check(x, ptr, size) \
137({ \
138 long __gu_err = -EFAULT; \
139 const __typeof__(*(ptr)) __user *__gu_addr = (ptr); \
140 if (access_ok(__gu_addr, size)) \
141 __get_user_size((x), __gu_addr, (size), __gu_err); \
142 else \
143 (x) = (__typeof__(*(ptr))) 0; \
144 __gu_err; \
145})
146
147extern long __get_user_bad(void);
148
149#define __get_user_size(x, ptr, size, retval) \
150do { \
151 retval = 0; \
152 switch (size) { \
153 case 1: __get_user_asm(x, ptr, retval, "l.lbz"); break; \
154 case 2: __get_user_asm(x, ptr, retval, "l.lhz"); break; \
155 case 4: __get_user_asm(x, ptr, retval, "l.lwz"); break; \
156 case 8: __get_user_asm2(x, ptr, retval); break; \
157 default: (x) = (__typeof__(*(ptr)))__get_user_bad(); \
158 } \
159} while (0)
160
161#define __get_user_asm(x, addr, err, op) \
162{ \
163 unsigned long __gu_tmp; \
164 __asm__ __volatile__( \
165 "1: "op" %1,0(%2)\n" \
166 "2:\n" \
167 ".section .fixup,\"ax\"\n" \
168 "3: l.addi %0,r0,%3\n" \
169 " l.addi %1,r0,0\n" \
170 " l.j 2b\n" \
171 " l.nop\n" \
172 ".previous\n" \
173 ".section __ex_table,\"a\"\n" \
174 " .align 2\n" \
175 " .long 1b,3b\n" \
176 ".previous" \
177 : "=r"(err), "=r"(__gu_tmp) \
178 : "r"(addr), "i"(-EFAULT), "0"(err)); \
179 (x) = (__typeof__(*(addr)))__gu_tmp; \
180}
181
182#define __get_user_asm2(x, addr, err) \
183{ \
184 unsigned long long __gu_tmp; \
185 __asm__ __volatile__( \
186 "1: l.lwz %1,0(%2)\n" \
187 "2: l.lwz %H1,4(%2)\n" \
188 "3:\n" \
189 ".section .fixup,\"ax\"\n" \
190 "4: l.addi %0,r0,%3\n" \
191 " l.addi %1,r0,0\n" \
192 " l.addi %H1,r0,0\n" \
193 " l.j 3b\n" \
194 " l.nop\n" \
195 ".previous\n" \
196 ".section __ex_table,\"a\"\n" \
197 " .align 2\n" \
198 " .long 1b,4b\n" \
199 " .long 2b,4b\n" \
200 ".previous" \
201 : "=r"(err), "=&r"(__gu_tmp) \
202 : "r"(addr), "i"(-EFAULT), "0"(err)); \
203 (x) = (__typeof__(*(addr)))( \
204 (__typeof__((x)-(x)))__gu_tmp); \
205}
206
207/* more complex routines */
208
209extern unsigned long __must_check
210__copy_tofrom_user(void *to, const void *from, unsigned long size);
211static inline unsigned long
212raw_copy_from_user(void *to, const void __user *from, unsigned long size)
213{
214 return __copy_tofrom_user(to, (__force const void *)from, size);
215}
216static inline unsigned long
217raw_copy_to_user(void __user *to, const void *from, unsigned long size)
218{
219 return __copy_tofrom_user((__force void *)to, from, size);
220}
221#define INLINE_COPY_FROM_USER
222#define INLINE_COPY_TO_USER
223
224extern unsigned long __clear_user(void __user *addr, unsigned long size);
225
226static inline __must_check unsigned long
227clear_user(void __user *addr, unsigned long size)
228{
229 if (likely(access_ok(addr, size)))
230 size = __clear_user(addr, size);
231 return size;
232}
233
234extern long strncpy_from_user(char *dest, const char __user *src, long count);
235
236extern __must_check long strnlen_user(const char __user *str, long n);
237
238#endif /* __ASM_OPENRISC_UACCESS_H */
1/*
2 * OpenRISC Linux
3 *
4 * Linux architectural port borrowing liberally from similar works of
5 * others. All original copyrights apply as per the original source
6 * declaration.
7 *
8 * OpenRISC implementation:
9 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
10 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
11 * et al.
12 *
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
17 */
18
19#ifndef __ASM_OPENRISC_UACCESS_H
20#define __ASM_OPENRISC_UACCESS_H
21
22/*
23 * User space memory access functions
24 */
25#include <linux/prefetch.h>
26#include <linux/string.h>
27#include <asm/page.h>
28#include <asm/extable.h>
29
30/*
31 * The fs value determines whether argument validity checking should be
32 * performed or not. If get_fs() == USER_DS, checking is performed, with
33 * get_fs() == KERNEL_DS, checking is bypassed.
34 *
35 * For historical reasons, these macros are grossly misnamed.
36 */
37
38/* addr_limit is the maximum accessible address for the task. we misuse
39 * the KERNEL_DS and USER_DS values to both assign and compare the
40 * addr_limit values through the equally misnamed get/set_fs macros.
41 * (see above)
42 */
43
44#define KERNEL_DS (~0UL)
45#define get_ds() (KERNEL_DS)
46
47#define USER_DS (TASK_SIZE)
48#define get_fs() (current_thread_info()->addr_limit)
49#define set_fs(x) (current_thread_info()->addr_limit = (x))
50
51#define segment_eq(a, b) ((a) == (b))
52
53/* Ensure that the range from addr to addr+size is all within the process'
54 * address space
55 */
56#define __range_ok(addr, size) (size <= get_fs() && addr <= (get_fs()-size))
57
58/* Ensure that addr is below task's addr_limit */
59#define __addr_ok(addr) ((unsigned long) addr < get_fs())
60
61#define access_ok(type, addr, size) \
62 __range_ok((unsigned long)addr, (unsigned long)size)
63
64/*
65 * These are the main single-value transfer routines. They automatically
66 * use the right size if we just have the right pointer type.
67 *
68 * This gets kind of ugly. We want to return _two_ values in "get_user()"
69 * and yet we don't want to do any pointers, because that is too much
70 * of a performance impact. Thus we have a few rather ugly macros here,
71 * and hide all the uglyness from the user.
72 *
73 * The "__xxx" versions of the user access functions are versions that
74 * do not verify the address space, that must have been done previously
75 * with a separate "access_ok()" call (this is used when we do multiple
76 * accesses to the same area of user memory).
77 *
78 * As we use the same address space for kernel and user data on the
79 * PowerPC, we can just do these as direct assignments. (Of course, the
80 * exception handling means that it's no longer "just"...)
81 */
82#define get_user(x, ptr) \
83 __get_user_check((x), (ptr), sizeof(*(ptr)))
84#define put_user(x, ptr) \
85 __put_user_check((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
86
87#define __get_user(x, ptr) \
88 __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
89#define __put_user(x, ptr) \
90 __put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))
91
92extern long __put_user_bad(void);
93
94#define __put_user_nocheck(x, ptr, size) \
95({ \
96 long __pu_err; \
97 __put_user_size((x), (ptr), (size), __pu_err); \
98 __pu_err; \
99})
100
101#define __put_user_check(x, ptr, size) \
102({ \
103 long __pu_err = -EFAULT; \
104 __typeof__(*(ptr)) *__pu_addr = (ptr); \
105 if (access_ok(VERIFY_WRITE, __pu_addr, size)) \
106 __put_user_size((x), __pu_addr, (size), __pu_err); \
107 __pu_err; \
108})
109
110#define __put_user_size(x, ptr, size, retval) \
111do { \
112 retval = 0; \
113 switch (size) { \
114 case 1: __put_user_asm(x, ptr, retval, "l.sb"); break; \
115 case 2: __put_user_asm(x, ptr, retval, "l.sh"); break; \
116 case 4: __put_user_asm(x, ptr, retval, "l.sw"); break; \
117 case 8: __put_user_asm2(x, ptr, retval); break; \
118 default: __put_user_bad(); \
119 } \
120} while (0)
121
122struct __large_struct {
123 unsigned long buf[100];
124};
125#define __m(x) (*(struct __large_struct *)(x))
126
127/*
128 * We don't tell gcc that we are accessing memory, but this is OK
129 * because we do not write to any memory gcc knows about, so there
130 * are no aliasing issues.
131 */
132#define __put_user_asm(x, addr, err, op) \
133 __asm__ __volatile__( \
134 "1: "op" 0(%2),%1\n" \
135 "2:\n" \
136 ".section .fixup,\"ax\"\n" \
137 "3: l.addi %0,r0,%3\n" \
138 " l.j 2b\n" \
139 " l.nop\n" \
140 ".previous\n" \
141 ".section __ex_table,\"a\"\n" \
142 " .align 2\n" \
143 " .long 1b,3b\n" \
144 ".previous" \
145 : "=r"(err) \
146 : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err))
147
148#define __put_user_asm2(x, addr, err) \
149 __asm__ __volatile__( \
150 "1: l.sw 0(%2),%1\n" \
151 "2: l.sw 4(%2),%H1\n" \
152 "3:\n" \
153 ".section .fixup,\"ax\"\n" \
154 "4: l.addi %0,r0,%3\n" \
155 " l.j 3b\n" \
156 " l.nop\n" \
157 ".previous\n" \
158 ".section __ex_table,\"a\"\n" \
159 " .align 2\n" \
160 " .long 1b,4b\n" \
161 " .long 2b,4b\n" \
162 ".previous" \
163 : "=r"(err) \
164 : "r"(x), "r"(addr), "i"(-EFAULT), "0"(err))
165
166#define __get_user_nocheck(x, ptr, size) \
167({ \
168 long __gu_err, __gu_val; \
169 __get_user_size(__gu_val, (ptr), (size), __gu_err); \
170 (x) = (__force __typeof__(*(ptr)))__gu_val; \
171 __gu_err; \
172})
173
174#define __get_user_check(x, ptr, size) \
175({ \
176 long __gu_err = -EFAULT, __gu_val = 0; \
177 const __typeof__(*(ptr)) * __gu_addr = (ptr); \
178 if (access_ok(VERIFY_READ, __gu_addr, size)) \
179 __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
180 (x) = (__force __typeof__(*(ptr)))__gu_val; \
181 __gu_err; \
182})
183
184extern long __get_user_bad(void);
185
186#define __get_user_size(x, ptr, size, retval) \
187do { \
188 retval = 0; \
189 switch (size) { \
190 case 1: __get_user_asm(x, ptr, retval, "l.lbz"); break; \
191 case 2: __get_user_asm(x, ptr, retval, "l.lhz"); break; \
192 case 4: __get_user_asm(x, ptr, retval, "l.lwz"); break; \
193 case 8: __get_user_asm2(x, ptr, retval); break; \
194 default: (x) = __get_user_bad(); \
195 } \
196} while (0)
197
198#define __get_user_asm(x, addr, err, op) \
199 __asm__ __volatile__( \
200 "1: "op" %1,0(%2)\n" \
201 "2:\n" \
202 ".section .fixup,\"ax\"\n" \
203 "3: l.addi %0,r0,%3\n" \
204 " l.addi %1,r0,0\n" \
205 " l.j 2b\n" \
206 " l.nop\n" \
207 ".previous\n" \
208 ".section __ex_table,\"a\"\n" \
209 " .align 2\n" \
210 " .long 1b,3b\n" \
211 ".previous" \
212 : "=r"(err), "=r"(x) \
213 : "r"(addr), "i"(-EFAULT), "0"(err))
214
215#define __get_user_asm2(x, addr, err) \
216 __asm__ __volatile__( \
217 "1: l.lwz %1,0(%2)\n" \
218 "2: l.lwz %H1,4(%2)\n" \
219 "3:\n" \
220 ".section .fixup,\"ax\"\n" \
221 "4: l.addi %0,r0,%3\n" \
222 " l.addi %1,r0,0\n" \
223 " l.addi %H1,r0,0\n" \
224 " l.j 3b\n" \
225 " l.nop\n" \
226 ".previous\n" \
227 ".section __ex_table,\"a\"\n" \
228 " .align 2\n" \
229 " .long 1b,4b\n" \
230 " .long 2b,4b\n" \
231 ".previous" \
232 : "=r"(err), "=&r"(x) \
233 : "r"(addr), "i"(-EFAULT), "0"(err))
234
235/* more complex routines */
236
237extern unsigned long __must_check
238__copy_tofrom_user(void *to, const void *from, unsigned long size);
239static inline unsigned long
240raw_copy_from_user(void *to, const void __user *from, unsigned long size)
241{
242 return __copy_tofrom_user(to, (__force const void *)from, size);
243}
244static inline unsigned long
245raw_copy_to_user(void *to, const void __user *from, unsigned long size)
246{
247 return __copy_tofrom_user((__force void *)to, from, size);
248}
249#define INLINE_COPY_FROM_USER
250#define INLINE_COPY_TO_USER
251
252extern unsigned long __clear_user(void *addr, unsigned long size);
253
254static inline __must_check unsigned long
255clear_user(void *addr, unsigned long size)
256{
257 if (likely(access_ok(VERIFY_WRITE, addr, size)))
258 size = __clear_user(addr, size);
259 return size;
260}
261
262#define user_addr_max() \
263 (uaccess_kernel() ? ~0UL : TASK_SIZE)
264
265extern long strncpy_from_user(char *dest, const char __user *src, long count);
266
267extern __must_check long strnlen_user(const char __user *str, long n);
268
269#endif /* __ASM_OPENRISC_UACCESS_H */