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1da177e4 LT |
1 | #ifndef _ASMARM_UACCESS_H |
2 | #define _ASMARM_UACCESS_H | |
3 | ||
4 | /* | |
5 | * User space memory access functions | |
6 | */ | |
7 | #include <linux/sched.h> | |
8 | #include <asm/errno.h> | |
9 | ||
10 | #define VERIFY_READ 0 | |
11 | #define VERIFY_WRITE 1 | |
12 | ||
13 | /* | |
14 | * The exception table consists of pairs of addresses: the first is the | |
15 | * address of an instruction that is allowed to fault, and the second is | |
16 | * the address at which the program should continue. No registers are | |
17 | * modified, so it is entirely up to the continuation code to figure out | |
18 | * what to do. | |
19 | * | |
20 | * All the routines below use bits of fixup code that are out of line | |
21 | * with the main instruction path. This means when everything is well, | |
22 | * we don't even have to jump over them. Further, they do not intrude | |
23 | * on our cache or tlb entries. | |
24 | */ | |
25 | ||
26 | struct exception_table_entry | |
27 | { | |
28 | unsigned long insn, fixup; | |
29 | }; | |
30 | ||
31 | /* Returns 0 if exception not found and fixup otherwise. */ | |
32 | extern unsigned long search_exception_table(unsigned long); | |
33 | extern int fixup_exception(struct pt_regs *regs); | |
34 | ||
35 | #define get_ds() (KERNEL_DS) | |
36 | #define get_fs() (current_thread_info()->addr_limit) | |
37 | #define segment_eq(a,b) ((a) == (b)) | |
38 | ||
39 | #include <asm/uaccess-asm.h> | |
40 | ||
41 | #define access_ok(type,addr,size) (__range_ok(addr,size) == 0) | |
42 | ||
1da177e4 LT |
43 | /* |
44 | * Single-value transfer routines. They automatically use the right | |
45 | * size if we just have the right pointer type. Note that the functions | |
46 | * which read from user space (*get_*) need to take care not to leak | |
47 | * kernel data even if the calling code is buggy and fails to check | |
48 | * the return value. This means zeroing out the destination variable | |
49 | * or buffer on error. Normally this is done out of line by the | |
50 | * fixup code, but there are a few places where it intrudes on the | |
51 | * main code path. When we only write to user space, there is no | |
52 | * problem. | |
53 | * | |
54 | * The "__xxx" versions of the user access functions do not verify the | |
55 | * address space - it must have been done previously with a separate | |
56 | * "access_ok()" call. | |
57 | * | |
58 | * The "xxx_error" versions set the third argument to EFAULT if an | |
59 | * error occurs, and leave it unchanged on success. Note that these | |
60 | * versions are void (ie, don't return a value as such). | |
61 | */ | |
62 | ||
63 | extern int __get_user_1(void *); | |
64 | extern int __get_user_2(void *); | |
65 | extern int __get_user_4(void *); | |
66 | extern int __get_user_8(void *); | |
67 | extern int __get_user_bad(void); | |
68 | ||
69 | #define __get_user_x(__r1,__p,__e,__s,__i...) \ | |
70 | __asm__ __volatile__ ("bl __get_user_" #__s \ | |
71 | : "=&r" (__e), "=r" (__r1) \ | |
72 | : "0" (__p) \ | |
73 | : __i) | |
74 | ||
75 | #define get_user(x,p) \ | |
76 | ({ \ | |
77 | const register typeof(*(p)) *__p asm("r0") = (p); \ | |
78 | register typeof(*(p)) __r1 asm("r1"); \ | |
79 | register int __e asm("r0"); \ | |
80 | switch (sizeof(*(p))) { \ | |
81 | case 1: \ | |
82 | __get_user_x(__r1, __p, __e, 1, "lr"); \ | |
83 | break; \ | |
84 | case 2: \ | |
85 | __get_user_x(__r1, __p, __e, 2, "r2", "lr"); \ | |
86 | break; \ | |
87 | case 4: \ | |
88 | __get_user_x(__r1, __p, __e, 4, "lr"); \ | |
89 | break; \ | |
90 | case 8: \ | |
91 | __get_user_x(__r1, __p, __e, 8, "lr"); \ | |
92 | break; \ | |
93 | default: __e = __get_user_bad(); break; \ | |
94 | } \ | |
95 | x = __r1; \ | |
96 | __e; \ | |
97 | }) | |
98 | ||
99 | ||
100 | #define __get_user(x,ptr) \ | |
101 | ({ \ | |
102 | long __gu_err = 0; \ | |
103 | __get_user_err((x),(ptr),__gu_err); \ | |
104 | __gu_err; \ | |
105 | }) | |
106 | ||
107 | #define __get_user_error(x,ptr,err) \ | |
108 | ({ \ | |
109 | __get_user_err((x),(ptr),err); \ | |
110 | (void) 0; \ | |
111 | }) | |
112 | ||
113 | #define __get_user_err(x,ptr,err) \ | |
114 | do { \ | |
115 | unsigned long __gu_addr = (unsigned long)(ptr); \ | |
116 | unsigned long __gu_val; \ | |
117 | switch (sizeof(*(ptr))) { \ | |
118 | case 1: __get_user_asm_byte(__gu_val,__gu_addr,err); break; \ | |
119 | case 2: __get_user_asm_half(__gu_val,__gu_addr,err); break; \ | |
120 | case 4: __get_user_asm_word(__gu_val,__gu_addr,err); break; \ | |
121 | default: (__gu_val) = __get_user_bad(); \ | |
122 | } \ | |
123 | (x) = (__typeof__(*(ptr)))__gu_val; \ | |
124 | } while (0) | |
125 | ||
126 | extern int __put_user_1(void *, unsigned int); | |
127 | extern int __put_user_2(void *, unsigned int); | |
128 | extern int __put_user_4(void *, unsigned int); | |
129 | extern int __put_user_8(void *, unsigned long long); | |
130 | extern int __put_user_bad(void); | |
131 | ||
132 | #define __put_user_x(__r1,__p,__e,__s) \ | |
133 | __asm__ __volatile__ ( \ | |
134 | __asmeq("%0", "r0") __asmeq("%2", "r1") \ | |
135 | "bl __put_user_" #__s \ | |
136 | : "=&r" (__e) \ | |
137 | : "0" (__p), "r" (__r1) \ | |
138 | : "ip", "lr", "cc") | |
139 | ||
140 | #define put_user(x,p) \ | |
141 | ({ \ | |
142 | const register typeof(*(p)) __r1 asm("r1") = (x); \ | |
143 | const register typeof(*(p)) *__p asm("r0") = (p); \ | |
144 | register int __e asm("r0"); \ | |
145 | switch (sizeof(*(__p))) { \ | |
146 | case 1: \ | |
147 | __put_user_x(__r1, __p, __e, 1); \ | |
148 | break; \ | |
149 | case 2: \ | |
150 | __put_user_x(__r1, __p, __e, 2); \ | |
151 | break; \ | |
152 | case 4: \ | |
153 | __put_user_x(__r1, __p, __e, 4); \ | |
154 | break; \ | |
155 | case 8: \ | |
156 | __put_user_x(__r1, __p, __e, 8); \ | |
157 | break; \ | |
158 | default: __e = __put_user_bad(); break; \ | |
159 | } \ | |
160 | __e; \ | |
161 | }) | |
162 | ||
163 | #if 0 | |
164 | /********************* OLD METHOD *******************/ | |
165 | #define __put_user_x(__r1,__p,__e,__s,__i...) \ | |
166 | __asm__ __volatile__ ("bl __put_user_" #__s \ | |
167 | : "=&r" (__e) \ | |
168 | : "0" (__p), "r" (__r1) \ | |
169 | : __i) | |
170 | ||
171 | #define put_user(x,p) \ | |
172 | ({ \ | |
173 | const register typeof(*(p)) __r1 asm("r1") = (x); \ | |
174 | const register typeof(*(p)) *__p asm("r0") = (p); \ | |
175 | register int __e asm("r0"); \ | |
176 | switch (sizeof(*(p))) { \ | |
177 | case 1: \ | |
178 | __put_user_x(__r1, __p, __e, 1, "r2", "lr"); \ | |
179 | break; \ | |
180 | case 2: \ | |
181 | __put_user_x(__r1, __p, __e, 2, "r2", "lr"); \ | |
182 | break; \ | |
183 | case 4: \ | |
184 | __put_user_x(__r1, __p, __e, 4, "r2", "lr"); \ | |
185 | break; \ | |
186 | case 8: \ | |
187 | __put_user_x(__r1, __p, __e, 8, "r2", "ip", "lr"); \ | |
188 | break; \ | |
189 | default: __e = __put_user_bad(); break; \ | |
190 | } \ | |
191 | __e; \ | |
192 | }) | |
193 | /*************************************************/ | |
194 | #endif | |
195 | ||
196 | #define __put_user(x,ptr) \ | |
197 | ({ \ | |
198 | long __pu_err = 0; \ | |
199 | __put_user_err((x),(ptr),__pu_err); \ | |
200 | __pu_err; \ | |
201 | }) | |
202 | ||
203 | #define __put_user_error(x,ptr,err) \ | |
204 | ({ \ | |
205 | __put_user_err((x),(ptr),err); \ | |
206 | (void) 0; \ | |
207 | }) | |
208 | ||
209 | #define __put_user_err(x,ptr,err) \ | |
210 | do { \ | |
211 | unsigned long __pu_addr = (unsigned long)(ptr); \ | |
212 | __typeof__(*(ptr)) __pu_val = (x); \ | |
213 | switch (sizeof(*(ptr))) { \ | |
214 | case 1: __put_user_asm_byte(__pu_val,__pu_addr,err); break; \ | |
215 | case 2: __put_user_asm_half(__pu_val,__pu_addr,err); break; \ | |
216 | case 4: __put_user_asm_word(__pu_val,__pu_addr,err); break; \ | |
217 | case 8: __put_user_asm_dword(__pu_val,__pu_addr,err); break; \ | |
218 | default: __put_user_bad(); \ | |
219 | } \ | |
220 | } while (0) | |
221 | ||
222 | static __inline__ unsigned long copy_from_user(void *to, const void *from, unsigned long n) | |
223 | { | |
224 | if (access_ok(VERIFY_READ, from, n)) | |
225 | __do_copy_from_user(to, from, n); | |
226 | else /* security hole - plug it */ | |
227 | memzero(to, n); | |
228 | return n; | |
229 | } | |
230 | ||
231 | static __inline__ unsigned long __copy_from_user(void *to, const void *from, unsigned long n) | |
232 | { | |
233 | __do_copy_from_user(to, from, n); | |
234 | return n; | |
235 | } | |
236 | ||
237 | static __inline__ unsigned long copy_to_user(void *to, const void *from, unsigned long n) | |
238 | { | |
239 | if (access_ok(VERIFY_WRITE, to, n)) | |
240 | __do_copy_to_user(to, from, n); | |
241 | return n; | |
242 | } | |
243 | ||
244 | static __inline__ unsigned long __copy_to_user(void *to, const void *from, unsigned long n) | |
245 | { | |
246 | __do_copy_to_user(to, from, n); | |
247 | return n; | |
248 | } | |
249 | ||
250 | #define __copy_to_user_inatomic __copy_to_user | |
251 | #define __copy_from_user_inatomic __copy_from_user | |
252 | ||
253 | static __inline__ unsigned long clear_user (void *to, unsigned long n) | |
254 | { | |
255 | if (access_ok(VERIFY_WRITE, to, n)) | |
256 | __do_clear_user(to, n); | |
257 | return n; | |
258 | } | |
259 | ||
260 | static __inline__ unsigned long __clear_user (void *to, unsigned long n) | |
261 | { | |
262 | __do_clear_user(to, n); | |
263 | return n; | |
264 | } | |
265 | ||
266 | static __inline__ long strncpy_from_user (char *dst, const char *src, long count) | |
267 | { | |
268 | long res = -EFAULT; | |
269 | if (access_ok(VERIFY_READ, src, 1)) | |
270 | __do_strncpy_from_user(dst, src, count, res); | |
271 | return res; | |
272 | } | |
273 | ||
274 | static __inline__ long __strncpy_from_user (char *dst, const char *src, long count) | |
275 | { | |
276 | long res; | |
277 | __do_strncpy_from_user(dst, src, count, res); | |
278 | return res; | |
279 | } | |
280 | ||
281 | #define strlen_user(s) strnlen_user(s, ~0UL >> 1) | |
282 | ||
283 | static inline long strnlen_user(const char *s, long n) | |
284 | { | |
285 | unsigned long res = 0; | |
286 | ||
287 | if (__addr_ok(s)) | |
288 | __do_strnlen_user(s, n, res); | |
289 | ||
290 | return res; | |
291 | } | |
292 | ||
293 | #endif /* _ASMARM_UACCESS_H */ |