1#ifndef __ASM_GENERIC_UACCESS_H
2#define __ASM_GENERIC_UACCESS_H
3
4
5
6
7
8
9#include <linux/sched.h>
10#include <linux/mm.h>
11#include <linux/string.h>
12
13#include <asm/segment.h>
14
15#define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
16
17#ifndef KERNEL_DS
18#define KERNEL_DS MAKE_MM_SEG(~0UL)
19#endif
20
21#ifndef USER_DS
22#define USER_DS MAKE_MM_SEG(TASK_SIZE - 1)
23#endif
24
25#ifndef get_fs
26#define get_ds() (KERNEL_DS)
27#define get_fs() (current_thread_info()->addr_limit)
28
29static inline void set_fs(mm_segment_t fs)
30{
31 current_thread_info()->addr_limit = fs;
32}
33#endif
34
35#define segment_eq(a, b) ((a).seg == (b).seg)
36
37#define VERIFY_READ 0
38#define VERIFY_WRITE 1
39
40#define access_ok(type, addr, size) __access_ok((unsigned long)(addr),(size))
41
42
43
44
45
46#ifndef __access_ok
47static inline int __access_ok(unsigned long addr, unsigned long size)
48{
49 return 1;
50}
51#endif
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66struct exception_table_entry
67{
68 unsigned long insn, fixup;
69};
70
71
72extern unsigned long search_exception_table(unsigned long);
73
74
75
76
77#ifndef __copy_from_user
78static inline __must_check long __copy_from_user(void *to,
79 const void __user * from, unsigned long n)
80{
81 if (__builtin_constant_p(n)) {
82 switch(n) {
83 case 1:
84 *(u8 *)to = *(u8 __force *)from;
85 return 0;
86 case 2:
87 *(u16 *)to = *(u16 __force *)from;
88 return 0;
89 case 4:
90 *(u32 *)to = *(u32 __force *)from;
91 return 0;
92#ifdef CONFIG_64BIT
93 case 8:
94 *(u64 *)to = *(u64 __force *)from;
95 return 0;
96#endif
97 default:
98 break;
99 }
100 }
101
102 memcpy(to, (const void __force *)from, n);
103 return 0;
104}
105#endif
106
107#ifndef __copy_to_user
108static inline __must_check long __copy_to_user(void __user *to,
109 const void *from, unsigned long n)
110{
111 if (__builtin_constant_p(n)) {
112 switch(n) {
113 case 1:
114 *(u8 __force *)to = *(u8 *)from;
115 return 0;
116 case 2:
117 *(u16 __force *)to = *(u16 *)from;
118 return 0;
119 case 4:
120 *(u32 __force *)to = *(u32 *)from;
121 return 0;
122#ifdef CONFIG_64BIT
123 case 8:
124 *(u64 __force *)to = *(u64 *)from;
125 return 0;
126#endif
127 default:
128 break;
129 }
130 }
131
132 memcpy((void __force *)to, from, n);
133 return 0;
134}
135#endif
136
137
138
139
140
141
142
143#define __put_user(x, ptr) \
144({ \
145 __typeof__(*(ptr)) __x = (x); \
146 int __pu_err = -EFAULT; \
147 __chk_user_ptr(ptr); \
148 switch (sizeof (*(ptr))) { \
149 case 1: \
150 case 2: \
151 case 4: \
152 case 8: \
153 __pu_err = __put_user_fn(sizeof (*(ptr)), \
154 ptr, &__x); \
155 break; \
156 default: \
157 __put_user_bad(); \
158 break; \
159 } \
160 __pu_err; \
161})
162
163#define put_user(x, ptr) \
164({ \
165 might_sleep(); \
166 access_ok(VERIFY_WRITE, ptr, sizeof(*ptr)) ? \
167 __put_user(x, ptr) : \
168 -EFAULT; \
169})
170
171static inline int __put_user_fn(size_t size, void __user *ptr, void *x)
172{
173 size = __copy_to_user(ptr, x, size);
174 return size ? -EFAULT : size;
175}
176
177extern int __put_user_bad(void) __attribute__((noreturn));
178
179#define __get_user(x, ptr) \
180({ \
181 int __gu_err = -EFAULT; \
182 __chk_user_ptr(ptr); \
183 switch (sizeof(*(ptr))) { \
184 case 1: { \
185 unsigned char __x; \
186 __gu_err = __get_user_fn(sizeof (*(ptr)), \
187 ptr, &__x); \
188 (x) = *(__force __typeof__(*(ptr)) *) &__x; \
189 break; \
190 }; \
191 case 2: { \
192 unsigned short __x; \
193 __gu_err = __get_user_fn(sizeof (*(ptr)), \
194 ptr, &__x); \
195 (x) = *(__force __typeof__(*(ptr)) *) &__x; \
196 break; \
197 }; \
198 case 4: { \
199 unsigned int __x; \
200 __gu_err = __get_user_fn(sizeof (*(ptr)), \
201 ptr, &__x); \
202 (x) = *(__force __typeof__(*(ptr)) *) &__x; \
203 break; \
204 }; \
205 case 8: { \
206 unsigned long long __x; \
207 __gu_err = __get_user_fn(sizeof (*(ptr)), \
208 ptr, &__x); \
209 (x) = *(__force __typeof__(*(ptr)) *) &__x; \
210 break; \
211 }; \
212 default: \
213 __get_user_bad(); \
214 break; \
215 } \
216 __gu_err; \
217})
218
219#define get_user(x, ptr) \
220({ \
221 might_sleep(); \
222 access_ok(VERIFY_READ, ptr, sizeof(*ptr)) ? \
223 __get_user(x, ptr) : \
224 -EFAULT; \
225})
226
227static inline int __get_user_fn(size_t size, const void __user *ptr, void *x)
228{
229 size = __copy_from_user(x, ptr, size);
230 return size ? -EFAULT : size;
231}
232
233extern int __get_user_bad(void) __attribute__((noreturn));
234
235#ifndef __copy_from_user_inatomic
236#define __copy_from_user_inatomic __copy_from_user
237#endif
238
239#ifndef __copy_to_user_inatomic
240#define __copy_to_user_inatomic __copy_to_user
241#endif
242
243static inline long copy_from_user(void *to,
244 const void __user * from, unsigned long n)
245{
246 might_sleep();
247 if (access_ok(VERIFY_READ, from, n))
248 return __copy_from_user(to, from, n);
249 else
250 return n;
251}
252
253static inline long copy_to_user(void __user *to,
254 const void *from, unsigned long n)
255{
256 might_sleep();
257 if (access_ok(VERIFY_WRITE, to, n))
258 return __copy_to_user(to, from, n);
259 else
260 return n;
261}
262
263
264
265
266#ifndef __strncpy_from_user
267static inline long
268__strncpy_from_user(char *dst, const char __user *src, long count)
269{
270 char *tmp;
271 strncpy(dst, (const char __force *)src, count);
272 for (tmp = dst; *tmp && count > 0; tmp++, count--)
273 ;
274 return (tmp - dst);
275}
276#endif
277
278static inline long
279strncpy_from_user(char *dst, const char __user *src, long count)
280{
281 if (!access_ok(VERIFY_READ, src, 1))
282 return -EFAULT;
283 return __strncpy_from_user(dst, src, count);
284}
285
286
287
288
289
290
291#ifndef strnlen_user
292static inline long strnlen_user(const char __user *src, long n)
293{
294 if (!access_ok(VERIFY_READ, src, 1))
295 return 0;
296 return strlen((void * __force)src) + 1;
297}
298#endif
299
300static inline long strlen_user(const char __user *src)
301{
302 return strnlen_user(src, 32767);
303}
304
305
306
307
308#ifndef __clear_user
309static inline __must_check unsigned long
310__clear_user(void __user *to, unsigned long n)
311{
312 memset((void __force *)to, 0, n);
313 return 0;
314}
315#endif
316
317static inline __must_check unsigned long
318clear_user(void __user *to, unsigned long n)
319{
320 might_sleep();
321 if (!access_ok(VERIFY_WRITE, to, n))
322 return n;
323
324 return __clear_user(to, n);
325}
326
327#endif
328