vserver 2.0 rc7
[linux-2.6.git] / include / asm-sh64 / uaccess.h
1 #ifndef __ASM_SH64_UACCESS_H
2 #define __ASM_SH64_UACCESS_H
3
4 /*
5  * This file is subject to the terms and conditions of the GNU General Public
6  * License.  See the file "COPYING" in the main directory of this archive
7  * for more details.
8  *
9  * include/asm-sh64/uaccess.h
10  *
11  * Copyright (C) 2000, 2001  Paolo Alberelli
12  * Copyright (C) 2003, 2004  Paul Mundt
13  *
14  * User space memory access functions
15  *
16  * Copyright (C) 1999  Niibe Yutaka
17  *
18  *  Based on:
19  *     MIPS implementation version 1.15 by
20  *              Copyright (C) 1996, 1997, 1998 by Ralf Baechle
21  *     and i386 version.
22  *
23  */
24
25 #include <linux/errno.h>
26 #include <linux/sched.h>
27
28 #define VERIFY_READ    0
29 #define VERIFY_WRITE   1
30
31 /*
32  * The fs value determines whether argument validity checking should be
33  * performed or not.  If get_fs() == USER_DS, checking is performed, with
34  * get_fs() == KERNEL_DS, checking is bypassed.
35  *
36  * For historical reasons (Data Segment Register?), these macros are misnamed.
37  */
38
39 #define MAKE_MM_SEG(s)  ((mm_segment_t) { (s) })
40
41 #define KERNEL_DS       MAKE_MM_SEG(0xFFFFFFFF)
42 #define USER_DS         MAKE_MM_SEG(0x80000000)
43
44 #define get_ds()        (KERNEL_DS)
45 #define get_fs()        (current_thread_info()->addr_limit)
46 #define set_fs(x)       (current_thread_info()->addr_limit=(x))
47
48 #define segment_eq(a,b) ((a).seg == (b).seg)
49
50 #define __addr_ok(addr) ((unsigned long)(addr) < (current_thread_info()->addr_limit.seg))
51
52 /*
53  * Uhhuh, this needs 33-bit arithmetic. We have a carry..
54  *
55  * sum := addr + size;  carry? --> flag = true;
56  * if (sum >= addr_limit) flag = true;
57  */
58 #define __range_ok(addr,size) (((unsigned long) (addr) + (size) < (current_thread_info()->addr_limit.seg)) ? 0 : 1)
59
60 #define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
61 #define __access_ok(addr,size) (__range_ok(addr,size) == 0)
62
63 /* this function will go away soon - use access_ok() instead */
64 extern inline int __deprecated verify_area(int type, const void __user * addr, unsigned long size)
65 {
66         return access_ok(type,addr,size) ? 0 : -EFAULT;
67 }
68
69 /*
70  * Uh, these should become the main single-value transfer routines ...
71  * They automatically use the right size if we just have the right
72  * pointer type ...
73  *
74  * As MIPS uses the same address space for kernel and user data, we
75  * can just do these as direct assignments.
76  *
77  * Careful to not
78  * (a) re-use the arguments for side effects (sizeof is ok)
79  * (b) require any knowledge of processes at this stage
80  */
81 #define put_user(x,ptr) __put_user_check((x),(ptr),sizeof(*(ptr)))
82 #define get_user(x,ptr) __get_user_check((x),(ptr),sizeof(*(ptr)))
83
84 /*
85  * The "__xxx" versions do not do address space checking, useful when
86  * doing multiple accesses to the same area (the user has to do the
87  * checks by hand with "access_ok()")
88  */
89 #define __put_user(x,ptr) __put_user_nocheck((x),(ptr),sizeof(*(ptr)))
90 #define __get_user(x,ptr) __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
91
92 /*
93  * The "xxx_ret" versions return constant specified in third argument, if
94  * something bad happens. These macros can be optimized for the
95  * case of just returning from the function xxx_ret is used.
96  */
97
98 #define put_user_ret(x,ptr,ret) ({ \
99 if (put_user(x,ptr)) return ret; })
100
101 #define get_user_ret(x,ptr,ret) ({ \
102 if (get_user(x,ptr)) return ret; })
103
104 #define __put_user_ret(x,ptr,ret) ({ \
105 if (__put_user(x,ptr)) return ret; })
106
107 #define __get_user_ret(x,ptr,ret) ({ \
108 if (__get_user(x,ptr)) return ret; })
109
110 struct __large_struct { unsigned long buf[100]; };
111 #define __m(x) (*(struct __large_struct *)(x))
112
113 #define __get_user_size(x,ptr,size,retval)                      \
114 do {                                                            \
115         retval = 0;                                             \
116         switch (size) {                                         \
117         case 1:                                                 \
118                 retval = __get_user_asm_b(x, ptr);              \
119                 break;                                          \
120         case 2:                                                 \
121                 retval = __get_user_asm_w(x, ptr);              \
122                 break;                                          \
123         case 4:                                                 \
124                 retval = __get_user_asm_l(x, ptr);              \
125                 break;                                          \
126         case 8:                                                 \
127                 retval = __get_user_asm_q(x, ptr);              \
128                 break;                                          \
129         default:                                                \
130                 __get_user_unknown();                           \
131                 break;                                          \
132         }                                                       \
133 } while (0)
134
135 #define __get_user_nocheck(x,ptr,size)                          \
136 ({                                                              \
137         long __gu_addr = (long)(ptr);                           \
138         long __gu_err;                                          \
139         __typeof(*(ptr)) __gu_val;                              \
140         __asm__ ("":"=r" (__gu_val));                           \
141         __asm__ ("":"=r" (__gu_err));                           \
142         __get_user_size((void *)&__gu_val, __gu_addr, (size), __gu_err); \
143         (x) = (__typeof__(*(ptr))) __gu_val;                    \
144         __gu_err;                                               \
145 })
146
147 #define __get_user_check(x,ptr,size)                            \
148 ({                                                              \
149         long __gu_addr = (long)(ptr);                           \
150         long __gu_err = -EFAULT;                                \
151         __typeof(*(ptr)) __gu_val;                              \
152         __asm__ ("":"=r" (__gu_val));                           \
153         __asm__ ("":"=r" (__gu_err));                           \
154         if (__access_ok(__gu_addr, (size)))                     \
155                 __get_user_size((void *)&__gu_val, __gu_addr, (size), __gu_err); \
156         (x) = (__typeof__(*(ptr))) __gu_val;                    \
157         __gu_err;                                               \
158 })
159
160 extern long __get_user_asm_b(void *, long);
161 extern long __get_user_asm_w(void *, long);
162 extern long __get_user_asm_l(void *, long);
163 extern long __get_user_asm_q(void *, long);
164 extern void __get_user_unknown(void);
165
166 #define __put_user_size(x,ptr,size,retval)                      \
167 do {                                                            \
168         retval = 0;                                             \
169         switch (size) {                                         \
170         case 1:                                                 \
171                 retval = __put_user_asm_b(x, ptr);              \
172                 break;                                          \
173         case 2:                                                 \
174                 retval = __put_user_asm_w(x, ptr);              \
175                 break;                                          \
176         case 4:                                                 \
177                 retval = __put_user_asm_l(x, ptr);              \
178                 break;                                          \
179         case 8:                                                 \
180                 retval = __put_user_asm_q(x, ptr);              \
181                 break;                                          \
182         default:                                                \
183                 __put_user_unknown();                           \
184         }                                                       \
185 } while (0)
186
187 #define __put_user_nocheck(x,ptr,size)                          \
188 ({                                                              \
189         long __pu_err;                                          \
190         __typeof__(*(ptr)) __pu_val = (x);                      \
191         __put_user_size((void *)&__pu_val, (long)(ptr), (size), __pu_err); \
192         __pu_err;                                               \
193 })
194
195 #define __put_user_check(x,ptr,size)                            \
196 ({                                                              \
197         long __pu_err = -EFAULT;                                \
198         long __pu_addr = (long)(ptr);                           \
199         __typeof__(*(ptr)) __pu_val = (x);                      \
200                                                                 \
201         if (__access_ok(__pu_addr, (size)))                     \
202                 __put_user_size((void *)&__pu_val, __pu_addr, (size), __pu_err);\
203         __pu_err;                                               \
204 })
205
206 extern long __put_user_asm_b(void *, long);
207 extern long __put_user_asm_w(void *, long);
208 extern long __put_user_asm_l(void *, long);
209 extern long __put_user_asm_q(void *, long);
210 extern void __put_user_unknown(void);
211
212 \f
213 /* Generic arbitrary sized copy.  */
214 /* Return the number of bytes NOT copied */
215 /* XXX: should be such that: 4byte and the rest. */
216 extern __kernel_size_t __copy_user(void *__to, const void *__from, __kernel_size_t __n);
217
218 #define copy_to_user(to,from,n) ({ \
219 void *__copy_to = (void *) (to); \
220 __kernel_size_t __copy_size = (__kernel_size_t) (n); \
221 __kernel_size_t __copy_res; \
222 if(__copy_size && __access_ok((unsigned long)__copy_to, __copy_size)) { \
223 __copy_res = __copy_user(__copy_to, (void *) (from), __copy_size); \
224 } else __copy_res = __copy_size; \
225 __copy_res; })
226
227 #define copy_to_user_ret(to,from,n,retval) ({ \
228 if (copy_to_user(to,from,n)) \
229         return retval; \
230 })
231
232 #define __copy_to_user(to,from,n)               \
233         __copy_user((void *)(to),               \
234                     (void *)(from), n)
235
236 #define __copy_to_user_ret(to,from,n,retval) ({ \
237 if (__copy_to_user(to,from,n)) \
238         return retval; \
239 })
240
241 #define copy_from_user(to,from,n) ({ \
242 void *__copy_to = (void *) (to); \
243 void *__copy_from = (void *) (from); \
244 __kernel_size_t __copy_size = (__kernel_size_t) (n); \
245 __kernel_size_t __copy_res; \
246 if(__copy_size && __access_ok((unsigned long)__copy_from, __copy_size)) { \
247 __copy_res = __copy_user(__copy_to, __copy_from, __copy_size); \
248 } else __copy_res = __copy_size; \
249 __copy_res; })
250
251 #define copy_from_user_ret(to,from,n,retval) ({ \
252 if (copy_from_user(to,from,n)) \
253         return retval; \
254 })
255
256 #define __copy_from_user(to,from,n)             \
257         __copy_user((void *)(to),               \
258                     (void *)(from), n)
259
260 #define __copy_from_user_ret(to,from,n,retval) ({ \
261 if (__copy_from_user(to,from,n)) \
262         return retval; \
263 })
264
265 #define __copy_to_user_inatomic __copy_to_user
266 #define __copy_from_user_inatomic __copy_from_user
267
268 /* XXX: Not sure it works well..
269    should be such that: 4byte clear and the rest. */
270 extern __kernel_size_t __clear_user(void *addr, __kernel_size_t size);
271
272 #define clear_user(addr,n) ({ \
273 void * __cl_addr = (addr); \
274 unsigned long __cl_size = (n); \
275 if (__cl_size && __access_ok(((unsigned long)(__cl_addr)), __cl_size)) \
276 __cl_size = __clear_user(__cl_addr, __cl_size); \
277 __cl_size; })
278
279 extern int __strncpy_from_user(unsigned long __dest, unsigned long __src, int __count);
280
281 #define strncpy_from_user(dest,src,count) ({ \
282 unsigned long __sfu_src = (unsigned long) (src); \
283 int __sfu_count = (int) (count); \
284 long __sfu_res = -EFAULT; \
285 if(__access_ok(__sfu_src, __sfu_count)) { \
286 __sfu_res = __strncpy_from_user((unsigned long) (dest), __sfu_src, __sfu_count); \
287 } __sfu_res; })
288
289 #define strlen_user(str) strnlen_user(str, ~0UL >> 1)
290
291 /*
292  * Return the size of a string (including the ending 0!)
293  */
294 extern long __strnlen_user(const char *__s, long __n);
295
296 extern __inline__ long strnlen_user(const char *s, long n)
297 {
298         if (!__addr_ok(s))
299                 return 0;
300         else
301                 return __strnlen_user(s, n);
302 }
303
304 struct exception_table_entry
305 {
306         unsigned long insn, fixup;
307 };
308
309 #define ARCH_HAS_SEARCH_EXTABLE
310
311 /* If gcc inlines memset, it will use st.q instructions.  Therefore, we need
312    kmalloc allocations to be 8-byte aligned.  Without this, the alignment
313    becomes BYTE_PER_WORD i.e. only 4 (since sizeof(long)==sizeof(void*)==4 on
314    sh64 at the moment). */
315 #define ARCH_KMALLOC_MINALIGN 8
316
317 /*
318  * We want 8-byte alignment for the slab caches as well, otherwise we have
319  * the same BYTES_PER_WORD (sizeof(void *)) min align in kmem_cache_create().
320  */
321 #define ARCH_SLAB_MINALIGN 8
322
323 /* Returns 0 if exception not found and fixup.unit otherwise.  */
324 extern unsigned long search_exception_table(unsigned long addr);
325 extern const struct exception_table_entry *search_exception_tables (unsigned long addr);
326
327 #endif /* __ASM_SH64_UACCESS_H */