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[TG3]: Update version and reldate.
[linux-2.6.22.y-op.git] / include / asm-avr32 / uaccess.h
blob821deb5a9d2893a1255b2bd85d25f8319a5ed87c
1 /*
2 * Copyright (C) 2004-2006 Atmel Corporation
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 */
8 #ifndef __ASM_AVR32_UACCESS_H
9 #define __ASM_AVR32_UACCESS_H
10
11 #include <linux/errno.h>
12 #include <linux/sched.h>
13
14 #define VERIFY_READ 0
15 #define VERIFY_WRITE 1
16
17 typedef struct {
18 unsigned int is_user_space;
19 } mm_segment_t;
20
21 /*
22 * The fs value determines whether argument validity checking should be
23 * performed or not. If get_fs() == USER_DS, checking is performed, with
24 * get_fs() == KERNEL_DS, checking is bypassed.
25 *
26 * For historical reasons (Data Segment Register?), these macros are misnamed.
27 */
28 #define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
29 #define segment_eq(a,b) ((a).is_user_space == (b).is_user_space)
30
31 #define USER_ADDR_LIMIT 0x80000000
32
33 #define KERNEL_DS MAKE_MM_SEG(0)
34 #define USER_DS MAKE_MM_SEG(1)
35
36 #define get_ds() (KERNEL_DS)
37
38 static inline mm_segment_t get_fs(void)
39 {
40 return MAKE_MM_SEG(test_thread_flag(TIF_USERSPACE));
41 }
42
43 static inline void set_fs(mm_segment_t s)
44 {
45 if (s.is_user_space)
46 set_thread_flag(TIF_USERSPACE);
47 else
48 clear_thread_flag(TIF_USERSPACE);
49 }
50
51 /*
52 * Test whether a block of memory is a valid user space address.
53 * Returns 0 if the range is valid, nonzero otherwise.
54 *
55 * We do the following checks:
56 * 1. Is the access from kernel space?
57 * 2. Does (addr + size) set the carry bit?
58 * 3. Is (addr + size) a negative number (i.e. >= 0x80000000)?
59 *
60 * If yes on the first check, access is granted.
61 * If no on any of the others, access is denied.
62 */
63 #define __range_ok(addr, size) \
64 (test_thread_flag(TIF_USERSPACE) \
65 && (((unsigned long)(addr) >= 0x80000000) \
66 || ((unsigned long)(size) > 0x80000000) \
67 || (((unsigned long)(addr) + (unsigned long)(size)) > 0x80000000)))
68
69 #define access_ok(type, addr, size) (likely(__range_ok(addr, size) == 0))
70
71 static inline int
72 verify_area(int type, const void __user *addr, unsigned long size)
73 {
74 return access_ok(type, addr, size) ? 0 : -EFAULT;
75 }
76
77 /* Generic arbitrary sized copy. Return the number of bytes NOT copied */
78 extern __kernel_size_t __copy_user(void *to, const void *from,
79 __kernel_size_t n);
80
81 extern __kernel_size_t copy_to_user(void __user *to, const void *from,
82 __kernel_size_t n);
83 extern __kernel_size_t copy_from_user(void *to, const void __user *from,
84 __kernel_size_t n);
85
86 static inline __kernel_size_t __copy_to_user(void __user *to, const void *from,
87 __kernel_size_t n)
88 {
89 return __copy_user((void __force *)to, from, n);
90 }
91 static inline __kernel_size_t __copy_from_user(void *to,
92 const void __user *from,
93 __kernel_size_t n)
94 {
95 return __copy_user(to, (const void __force *)from, n);
96 }
97
98 #define __copy_to_user_inatomic __copy_to_user
99 #define __copy_from_user_inatomic __copy_from_user
100
101 /*
102 * put_user: - Write a simple value into user space.
103 * @x: Value to copy to user space.
104 * @ptr: Destination address, in user space.
105 *
106 * Context: User context only. This function may sleep.
107 *
108 * This macro copies a single simple value from kernel space to user
109 * space. It supports simple types like char and int, but not larger
110 * data types like structures or arrays.
111 *
112 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
113 * to the result of dereferencing @ptr.
114 *
115 * Returns zero on success, or -EFAULT on error.
116 */
117 #define put_user(x,ptr) \
118 __put_user_check((x),(ptr),sizeof(*(ptr)))
119
120 /*
121 * get_user: - Get a simple variable from user space.
122 * @x: Variable to store result.
123 * @ptr: Source address, in user space.
124 *
125 * Context: User context only. This function may sleep.
126 *
127 * This macro copies a single simple variable from user space to kernel
128 * space. It supports simple types like char and int, but not larger
129 * data types like structures or arrays.
130 *
131 * @ptr must have pointer-to-simple-variable type, and the result of
132 * dereferencing @ptr must be assignable to @x without a cast.
133 *
134 * Returns zero on success, or -EFAULT on error.
135 * On error, the variable @x is set to zero.
136 */
137 #define get_user(x,ptr) \
138 __get_user_check((x),(ptr),sizeof(*(ptr)))
139
140 /*
141 * __put_user: - Write a simple value into user space, with less checking.
142 * @x: Value to copy to user space.
143 * @ptr: Destination address, in user space.
144 *
145 * Context: User context only. This function may sleep.
146 *
147 * This macro copies a single simple value from kernel space to user
148 * space. It supports simple types like char and int, but not larger
149 * data types like structures or arrays.
150 *
151 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
152 * to the result of dereferencing @ptr.
153 *
154 * Caller must check the pointer with access_ok() before calling this
155 * function.
156 *
157 * Returns zero on success, or -EFAULT on error.
158 */
159 #define __put_user(x,ptr) \
160 __put_user_nocheck((x),(ptr),sizeof(*(ptr)))
161
162 /*
163 * __get_user: - Get a simple variable from user space, with less checking.
164 * @x: Variable to store result.
165 * @ptr: Source address, in user space.
166 *
167 * Context: User context only. This function may sleep.
168 *
169 * This macro copies a single simple variable from user space to kernel
170 * space. It supports simple types like char and int, but not larger
171 * data types like structures or arrays.
172 *
173 * @ptr must have pointer-to-simple-variable type, and the result of
174 * dereferencing @ptr must be assignable to @x without a cast.
175 *
176 * Caller must check the pointer with access_ok() before calling this
177 * function.
178 *
179 * Returns zero on success, or -EFAULT on error.
180 * On error, the variable @x is set to zero.
181 */
182 #define __get_user(x,ptr) \
183 __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
184
185 extern int __get_user_bad(void);
186 extern int __put_user_bad(void);
187
188 #define __get_user_nocheck(x, ptr, size) \
189 ({ \
190 typeof(*(ptr)) __gu_val = (typeof(*(ptr)) __force)0; \
191 int __gu_err = 0; \
192 \
193 switch (size) { \
194 case 1: __get_user_asm("ub", __gu_val, ptr, __gu_err); break; \
195 case 2: __get_user_asm("uh", __gu_val, ptr, __gu_err); break; \
196 case 4: __get_user_asm("w", __gu_val, ptr, __gu_err); break; \
197 case 8: __get_user_asm("d", __gu_val, ptr, __gu_err); break; \
198 default: __gu_err = __get_user_bad(); break; \
199 } \
200 \
201 x = __gu_val; \
202 __gu_err; \
203 })
204
205 #define __get_user_check(x, ptr, size) \
206 ({ \
207 typeof(*(ptr)) __gu_val = (typeof(*(ptr)) __force)0; \
208 const typeof(*(ptr)) __user * __gu_addr = (ptr); \
209 int __gu_err = 0; \
210 \
211 if (access_ok(VERIFY_READ, __gu_addr, size)) { \
212 switch (size) { \
213 case 1: \
214 __get_user_asm("ub", __gu_val, __gu_addr, \
215 __gu_err); \
216 break; \
217 case 2: \
218 __get_user_asm("uh", __gu_val, __gu_addr, \
219 __gu_err); \
220 break; \
221 case 4: \
222 __get_user_asm("w", __gu_val, __gu_addr, \
223 __gu_err); \
224 break; \
225 case 8: \
226 __get_user_asm("d", __gu_val, __gu_addr, \
227 __gu_err); \
228 break; \
229 default: \
230 __gu_err = __get_user_bad(); \
231 break; \
232 } \
233 } else { \
234 __gu_err = -EFAULT; \
235 } \
236 x = __gu_val; \
237 __gu_err; \
238 })
239
240 #define __get_user_asm(suffix, __gu_val, ptr, __gu_err) \
241 asm volatile( \
242 "1: ld." suffix " %1, %3 \n" \
243 "2: \n" \
244 " .section .fixup, \"ax\" \n" \
245 "3: mov %0, %4 \n" \
246 " rjmp 2b \n" \
247 " .previous \n" \
248 " .section __ex_table, \"a\" \n" \
249 " .long 1b, 3b \n" \
250 " .previous \n" \
251 : "=r"(__gu_err), "=r"(__gu_val) \
252 : "0"(__gu_err), "m"(*(ptr)), "i"(-EFAULT))
253
254 #define __put_user_nocheck(x, ptr, size) \
255 ({ \
256 typeof(*(ptr)) __pu_val; \
257 int __pu_err = 0; \
258 \
259 __pu_val = (x); \
260 switch (size) { \
261 case 1: __put_user_asm("b", ptr, __pu_val, __pu_err); break; \
262 case 2: __put_user_asm("h", ptr, __pu_val, __pu_err); break; \
263 case 4: __put_user_asm("w", ptr, __pu_val, __pu_err); break; \
264 case 8: __put_user_asm("d", ptr, __pu_val, __pu_err); break; \
265 default: __pu_err = __put_user_bad(); break; \
266 } \
267 __pu_err; \
268 })
269
270 #define __put_user_check(x, ptr, size) \
271 ({ \
272 typeof(*(ptr)) __pu_val; \
273 typeof(*(ptr)) __user *__pu_addr = (ptr); \
274 int __pu_err = 0; \
275 \
276 __pu_val = (x); \
277 if (access_ok(VERIFY_WRITE, __pu_addr, size)) { \
278 switch (size) { \
279 case 1: \
280 __put_user_asm("b", __pu_addr, __pu_val, \
281 __pu_err); \
282 break; \
283 case 2: \
284 __put_user_asm("h", __pu_addr, __pu_val, \
285 __pu_err); \
286 break; \
287 case 4: \
288 __put_user_asm("w", __pu_addr, __pu_val, \
289 __pu_err); \
290 break; \
291 case 8: \
292 __put_user_asm("d", __pu_addr, __pu_val, \
293 __pu_err); \
294 break; \
295 default: \
296 __pu_err = __put_user_bad(); \
297 break; \
298 } \
299 } else { \
300 __pu_err = -EFAULT; \
301 } \
302 __pu_err; \
303 })
304
305 #define __put_user_asm(suffix, ptr, __pu_val, __gu_err) \
306 asm volatile( \
307 "1: st." suffix " %1, %3 \n" \
308 "2: \n" \
309 " .section .fixup, \"ax\" \n" \
310 "3: mov %0, %4 \n" \
311 " rjmp 2b \n" \
312 " .previous \n" \
313 " .section __ex_table, \"a\" \n" \
314 " .long 1b, 3b \n" \
315 " .previous \n" \
316 : "=r"(__gu_err), "=m"(*(ptr)) \
317 : "0"(__gu_err), "r"(__pu_val), "i"(-EFAULT))
318
319 extern __kernel_size_t clear_user(void __user *addr, __kernel_size_t size);
320 extern __kernel_size_t __clear_user(void __user *addr, __kernel_size_t size);
321
322 extern long strncpy_from_user(char *dst, const char __user *src, long count);
323 extern long __strncpy_from_user(char *dst, const char __user *src, long count);
324
325 extern long strnlen_user(const char __user *__s, long __n);
326 extern long __strnlen_user(const char __user *__s, long __n);
327
328 #define strlen_user(s) strnlen_user(s, ~0UL >> 1)
329
330 struct exception_table_entry
331 {
332 unsigned long insn, fixup;
333 };
334
335 #endif /* __ASM_AVR32_UACCESS_H */
linux v2.6.22.y-op