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Merge branch 'x86/microcode' into x86/urgent, to pick up cleanup
[linux/fpc-iii.git] / arch / avr32 / include / asm / uaccess.h
blobb1ec1fa064632258ac1a4bb50b3b22416bd43c0f
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 /* Generic arbitrary sized copy. Return the number of bytes NOT copied */
72 extern __kernel_size_t __copy_user(void *to, const void *from,
73 __kernel_size_t n);
74
75 extern __kernel_size_t copy_to_user(void __user *to, const void *from,
76 __kernel_size_t n);
77 extern __kernel_size_t ___copy_from_user(void *to, const void __user *from,
78 __kernel_size_t n);
79
80 static inline __kernel_size_t __copy_to_user(void __user *to, const void *from,
81 __kernel_size_t n)
82 {
83 return __copy_user((void __force *)to, from, n);
84 }
85 static inline __kernel_size_t __copy_from_user(void *to,
86 const void __user *from,
87 __kernel_size_t n)
88 {
89 return __copy_user(to, (const void __force *)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 size_t res = ___copy_from_user(to, from, n);
96 if (unlikely(res))
97 memset(to + (n - res), 0, res);
98 return res;
99 }
100
101 #define __copy_to_user_inatomic __copy_to_user
102 #define __copy_from_user_inatomic __copy_from_user
103
104 /*
105 * put_user: - Write a simple value into user space.
106 * @x: Value to copy to user space.
107 * @ptr: Destination address, in user space.
108 *
109 * Context: User context only. This function may sleep if pagefaults are
110 * enabled.
111 *
112 * This macro copies a single simple value from kernel space to user
113 * space. It supports simple types like char and int, but not larger
114 * data types like structures or arrays.
115 *
116 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
117 * to the result of dereferencing @ptr.
118 *
119 * Returns zero on success, or -EFAULT on error.
120 */
121 #define put_user(x, ptr) \
122 __put_user_check((x), (ptr), sizeof(*(ptr)))
123
124 /*
125 * get_user: - Get a simple variable from user space.
126 * @x: Variable to store result.
127 * @ptr: Source address, in user space.
128 *
129 * Context: User context only. This function may sleep if pagefaults are
130 * enabled.
131 *
132 * This macro copies a single simple variable from user space to kernel
133 * space. It supports simple types like char and int, but not larger
134 * data types like structures or arrays.
135 *
136 * @ptr must have pointer-to-simple-variable type, and the result of
137 * dereferencing @ptr must be assignable to @x without a cast.
138 *
139 * Returns zero on success, or -EFAULT on error.
140 * On error, the variable @x is set to zero.
141 */
142 #define get_user(x, ptr) \
143 __get_user_check((x), (ptr), sizeof(*(ptr)))
144
145 /*
146 * __put_user: - Write a simple value into user space, with less checking.
147 * @x: Value to copy to user space.
148 * @ptr: Destination address, in user space.
149 *
150 * Context: User context only. This function may sleep if pagefaults are
151 * enabled.
152 *
153 * This macro copies a single simple value from kernel space to user
154 * space. It supports simple types like char and int, but not larger
155 * data types like structures or arrays.
156 *
157 * @ptr must have pointer-to-simple-variable type, and @x must be assignable
158 * to the result of dereferencing @ptr.
159 *
160 * Caller must check the pointer with access_ok() before calling this
161 * function.
162 *
163 * Returns zero on success, or -EFAULT on error.
164 */
165 #define __put_user(x, ptr) \
166 __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
167
168 /*
169 * __get_user: - Get a simple variable from user space, with less checking.
170 * @x: Variable to store result.
171 * @ptr: Source address, in user space.
172 *
173 * Context: User context only. This function may sleep if pagefaults are
174 * enabled.
175 *
176 * This macro copies a single simple variable from user space to kernel
177 * space. It supports simple types like char and int, but not larger
178 * data types like structures or arrays.
179 *
180 * @ptr must have pointer-to-simple-variable type, and the result of
181 * dereferencing @ptr must be assignable to @x without a cast.
182 *
183 * Caller must check the pointer with access_ok() before calling this
184 * function.
185 *
186 * Returns zero on success, or -EFAULT on error.
187 * On error, the variable @x is set to zero.
188 */
189 #define __get_user(x, ptr) \
190 __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
191
192 extern int __get_user_bad(void);
193 extern int __put_user_bad(void);
194
195 #define __get_user_nocheck(x, ptr, size) \
196 ({ \
197 unsigned long __gu_val = 0; \
198 int __gu_err = 0; \
199 \
200 switch (size) { \
201 case 1: __get_user_asm("ub", __gu_val, ptr, __gu_err); break; \
202 case 2: __get_user_asm("uh", __gu_val, ptr, __gu_err); break; \
203 case 4: __get_user_asm("w", __gu_val, ptr, __gu_err); break; \
204 default: __gu_err = __get_user_bad(); break; \
205 } \
206 \
207 x = (__force typeof(*(ptr)))__gu_val; \
208 __gu_err; \
209 })
210
211 #define __get_user_check(x, ptr, size) \
212 ({ \
213 unsigned long __gu_val = 0; \
214 const typeof(*(ptr)) __user * __gu_addr = (ptr); \
215 int __gu_err = 0; \
216 \
217 if (access_ok(VERIFY_READ, __gu_addr, size)) { \
218 switch (size) { \
219 case 1: \
220 __get_user_asm("ub", __gu_val, __gu_addr, \
221 __gu_err); \
222 break; \
223 case 2: \
224 __get_user_asm("uh", __gu_val, __gu_addr, \
225 __gu_err); \
226 break; \
227 case 4: \
228 __get_user_asm("w", __gu_val, __gu_addr, \
229 __gu_err); \
230 break; \
231 default: \
232 __gu_err = __get_user_bad(); \
233 break; \
234 } \
235 } else { \
236 __gu_err = -EFAULT; \
237 } \
238 x = (__force typeof(*(ptr)))__gu_val; \
239 __gu_err; \
240 })
241
242 #define __get_user_asm(suffix, __gu_val, ptr, __gu_err) \
243 asm volatile( \
244 "1: ld." suffix " %1, %3 \n" \
245 "2: \n" \
246 " .subsection 1 \n" \
247 "3: mov %0, %4 \n" \
248 " rjmp 2b \n" \
249 " .subsection 0 \n" \
250 " .section __ex_table, \"a\" \n" \
251 " .long 1b, 3b \n" \
252 " .previous \n" \
253 : "=r"(__gu_err), "=r"(__gu_val) \
254 : "0"(__gu_err), "m"(*(ptr)), "i"(-EFAULT))
255
256 #define __put_user_nocheck(x, ptr, size) \
257 ({ \
258 typeof(*(ptr)) __pu_val; \
259 int __pu_err = 0; \
260 \
261 __pu_val = (x); \
262 switch (size) { \
263 case 1: __put_user_asm("b", ptr, __pu_val, __pu_err); break; \
264 case 2: __put_user_asm("h", ptr, __pu_val, __pu_err); break; \
265 case 4: __put_user_asm("w", ptr, __pu_val, __pu_err); break; \
266 case 8: __put_user_asm("d", ptr, __pu_val, __pu_err); break; \
267 default: __pu_err = __put_user_bad(); break; \
268 } \
269 __pu_err; \
270 })
271
272 #define __put_user_check(x, ptr, size) \
273 ({ \
274 typeof(*(ptr)) __pu_val; \
275 typeof(*(ptr)) __user *__pu_addr = (ptr); \
276 int __pu_err = 0; \
277 \
278 __pu_val = (x); \
279 if (access_ok(VERIFY_WRITE, __pu_addr, size)) { \
280 switch (size) { \
281 case 1: \
282 __put_user_asm("b", __pu_addr, __pu_val, \
283 __pu_err); \
284 break; \
285 case 2: \
286 __put_user_asm("h", __pu_addr, __pu_val, \
287 __pu_err); \
288 break; \
289 case 4: \
290 __put_user_asm("w", __pu_addr, __pu_val, \
291 __pu_err); \
292 break; \
293 case 8: \
294 __put_user_asm("d", __pu_addr, __pu_val, \
295 __pu_err); \
296 break; \
297 default: \
298 __pu_err = __put_user_bad(); \
299 break; \
300 } \
301 } else { \
302 __pu_err = -EFAULT; \
303 } \
304 __pu_err; \
305 })
306
307 #define __put_user_asm(suffix, ptr, __pu_val, __gu_err) \
308 asm volatile( \
309 "1: st." suffix " %1, %3 \n" \
310 "2: \n" \
311 " .subsection 1 \n" \
312 "3: mov %0, %4 \n" \
313 " rjmp 2b \n" \
314 " .subsection 0 \n" \
315 " .section __ex_table, \"a\" \n" \
316 " .long 1b, 3b \n" \
317 " .previous \n" \
318 : "=r"(__gu_err), "=m"(*(ptr)) \
319 : "0"(__gu_err), "r"(__pu_val), "i"(-EFAULT))
320
321 extern __kernel_size_t clear_user(void __user *addr, __kernel_size_t size);
322 extern __kernel_size_t __clear_user(void __user *addr, __kernel_size_t size);
323
324 extern long strncpy_from_user(char *dst, const char __user *src, long count);
325 extern long __strncpy_from_user(char *dst, const char __user *src, long count);
326
327 extern long strnlen_user(const char __user *__s, long __n);
328 extern long __strnlen_user(const char __user *__s, long __n);
329
330 #define strlen_user(s) strnlen_user(s, ~0UL >> 1)
331
332 struct exception_table_entry
333 {
334 unsigned long insn, fixup;
335 };
336
337 #endif /* __ASM_AVR32_UACCESS_H */
Linux with added FPC-III support