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spi-topcliff-pch: supports a spi mode setup and bit order setup by IO control
[zen-stable.git] / arch / arm / include / asm / uaccess.h
blob2958976d867b4b9795a090cee9a6b9cacb646631
1 /*
2 * arch/arm/include/asm/uaccess.h
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 _ASMARM_UACCESS_H
9 #define _ASMARM_UACCESS_H
10
11 /*
12 * User space memory access functions
13 */
14 #include <linux/string.h>
15 #include <linux/thread_info.h>
16 #include <asm/errno.h>
17 #include <asm/memory.h>
18 #include <asm/domain.h>
19 #include <asm/system.h>
20 #include <asm/unified.h>
21
22 #define VERIFY_READ 0
23 #define VERIFY_WRITE 1
24
25 /*
26 * The exception table consists of pairs of addresses: the first is the
27 * address of an instruction that is allowed to fault, and the second is
28 * the address at which the program should continue. No registers are
29 * modified, so it is entirely up to the continuation code to figure out
30 * what to do.
31 *
32 * All the routines below use bits of fixup code that are out of line
33 * with the main instruction path. This means when everything is well,
34 * we don't even have to jump over them. Further, they do not intrude
35 * on our cache or tlb entries.
36 */
37
38 struct exception_table_entry
39 {
40 unsigned long insn, fixup;
41 };
42
43 extern int fixup_exception(struct pt_regs *regs);
44
45 /*
46 * These two are intentionally not defined anywhere - if the kernel
47 * code generates any references to them, that's a bug.
48 */
49 extern int __get_user_bad(void);
50 extern int __put_user_bad(void);
51
52 /*
53 * Note that this is actually 0x1,0000,0000
54 */
55 #define KERNEL_DS 0x00000000
56 #define get_ds() (KERNEL_DS)
57
58 #ifdef CONFIG_MMU
59
60 #define USER_DS TASK_SIZE
61 #define get_fs() (current_thread_info()->addr_limit)
62
63 static inline void set_fs(mm_segment_t fs)
64 {
65 current_thread_info()->addr_limit = fs;
66 modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER);
67 }
68
69 #define segment_eq(a,b) ((a) == (b))
70
71 #define __addr_ok(addr) ({ \
72 unsigned long flag; \
73 __asm__("cmp %2, %0; movlo %0, #0" \
74 : "=&r" (flag) \
75 : "0" (current_thread_info()->addr_limit), "r" (addr) \
76 : "cc"); \
77 (flag == 0); })
78
79 /* We use 33-bit arithmetic here... */
80 #define __range_ok(addr,size) ({ \
81 unsigned long flag, roksum; \
82 __chk_user_ptr(addr); \
83 __asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \
84 : "=&r" (flag), "=&r" (roksum) \
85 : "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \
86 : "cc"); \
87 flag; })
88
89 /*
90 * Single-value transfer routines. They automatically use the right
91 * size if we just have the right pointer type. Note that the functions
92 * which read from user space (*get_*) need to take care not to leak
93 * kernel data even if the calling code is buggy and fails to check
94 * the return value. This means zeroing out the destination variable
95 * or buffer on error. Normally this is done out of line by the
96 * fixup code, but there are a few places where it intrudes on the
97 * main code path. When we only write to user space, there is no
98 * problem.
99 */
100 extern int __get_user_1(void *);
101 extern int __get_user_2(void *);
102 extern int __get_user_4(void *);
103
104 #define __get_user_x(__r2,__p,__e,__s,__i...) \
105 __asm__ __volatile__ ( \
106 __asmeq("%0", "r0") __asmeq("%1", "r2") \
107 "bl __get_user_" #__s \
108 : "=&r" (__e), "=r" (__r2) \
109 : "0" (__p) \
110 : __i, "cc")
111
112 #define get_user(x,p) \
113 ({ \
114 register const typeof(*(p)) __user *__p asm("r0") = (p);\
115 register unsigned long __r2 asm("r2"); \
116 register int __e asm("r0"); \
117 switch (sizeof(*(__p))) { \
118 case 1: \
119 __get_user_x(__r2, __p, __e, 1, "lr"); \
120 break; \
121 case 2: \
122 __get_user_x(__r2, __p, __e, 2, "r3", "lr"); \
123 break; \
124 case 4: \
125 __get_user_x(__r2, __p, __e, 4, "lr"); \
126 break; \
127 default: __e = __get_user_bad(); break; \
128 } \
129 x = (typeof(*(p))) __r2; \
130 __e; \
131 })
132
133 extern int __put_user_1(void *, unsigned int);
134 extern int __put_user_2(void *, unsigned int);
135 extern int __put_user_4(void *, unsigned int);
136 extern int __put_user_8(void *, unsigned long long);
137
138 #define __put_user_x(__r2,__p,__e,__s) \
139 __asm__ __volatile__ ( \
140 __asmeq("%0", "r0") __asmeq("%2", "r2") \
141 "bl __put_user_" #__s \
142 : "=&r" (__e) \
143 : "0" (__p), "r" (__r2) \
144 : "ip", "lr", "cc")
145
146 #define put_user(x,p) \
147 ({ \
148 register const typeof(*(p)) __r2 asm("r2") = (x); \
149 register const typeof(*(p)) __user *__p asm("r0") = (p);\
150 register int __e asm("r0"); \
151 switch (sizeof(*(__p))) { \
152 case 1: \
153 __put_user_x(__r2, __p, __e, 1); \
154 break; \
155 case 2: \
156 __put_user_x(__r2, __p, __e, 2); \
157 break; \
158 case 4: \
159 __put_user_x(__r2, __p, __e, 4); \
160 break; \
161 case 8: \
162 __put_user_x(__r2, __p, __e, 8); \
163 break; \
164 default: __e = __put_user_bad(); break; \
165 } \
166 __e; \
167 })
168
169 #else /* CONFIG_MMU */
170
171 /*
172 * uClinux has only one addr space, so has simplified address limits.
173 */
174 #define USER_DS KERNEL_DS
175
176 #define segment_eq(a,b) (1)
177 #define __addr_ok(addr) (1)
178 #define __range_ok(addr,size) (0)
179 #define get_fs() (KERNEL_DS)
180
181 static inline void set_fs(mm_segment_t fs)
182 {
183 }
184
185 #define get_user(x,p) __get_user(x,p)
186 #define put_user(x,p) __put_user(x,p)
187
188 #endif /* CONFIG_MMU */
189
190 #define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
191
192 /*
193 * The "__xxx" versions of the user access functions do not verify the
194 * address space - it must have been done previously with a separate
195 * "access_ok()" call.
196 *
197 * The "xxx_error" versions set the third argument to EFAULT if an
198 * error occurs, and leave it unchanged on success. Note that these
199 * versions are void (ie, don't return a value as such).
200 */
201 #define __get_user(x,ptr) \
202 ({ \
203 long __gu_err = 0; \
204 __get_user_err((x),(ptr),__gu_err); \
205 __gu_err; \
206 })
207
208 #define __get_user_error(x,ptr,err) \
209 ({ \
210 __get_user_err((x),(ptr),err); \
211 (void) 0; \
212 })
213
214 #define __get_user_err(x,ptr,err) \
215 do { \
216 unsigned long __gu_addr = (unsigned long)(ptr); \
217 unsigned long __gu_val; \
218 __chk_user_ptr(ptr); \
219 switch (sizeof(*(ptr))) { \
220 case 1: __get_user_asm_byte(__gu_val,__gu_addr,err); break; \
221 case 2: __get_user_asm_half(__gu_val,__gu_addr,err); break; \
222 case 4: __get_user_asm_word(__gu_val,__gu_addr,err); break; \
223 default: (__gu_val) = __get_user_bad(); \
224 } \
225 (x) = (__typeof__(*(ptr)))__gu_val; \
226 } while (0)
227
228 #define __get_user_asm_byte(x,addr,err) \
229 __asm__ __volatile__( \
230 "1: " TUSER(ldrb) " %1,[%2],#0\n" \
231 "2:\n" \
232 " .pushsection .fixup,\"ax\"\n" \
233 " .align 2\n" \
234 "3: mov %0, %3\n" \
235 " mov %1, #0\n" \
236 " b 2b\n" \
237 " .popsection\n" \
238 " .pushsection __ex_table,\"a\"\n" \
239 " .align 3\n" \
240 " .long 1b, 3b\n" \
241 " .popsection" \
242 : "+r" (err), "=&r" (x) \
243 : "r" (addr), "i" (-EFAULT) \
244 : "cc")
245
246 #ifndef __ARMEB__
247 #define __get_user_asm_half(x,__gu_addr,err) \
248 ({ \
249 unsigned long __b1, __b2; \
250 __get_user_asm_byte(__b1, __gu_addr, err); \
251 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
252 (x) = __b1 | (__b2 << 8); \
253 })
254 #else
255 #define __get_user_asm_half(x,__gu_addr,err) \
256 ({ \
257 unsigned long __b1, __b2; \
258 __get_user_asm_byte(__b1, __gu_addr, err); \
259 __get_user_asm_byte(__b2, __gu_addr + 1, err); \
260 (x) = (__b1 << 8) | __b2; \
261 })
262 #endif
263
264 #define __get_user_asm_word(x,addr,err) \
265 __asm__ __volatile__( \
266 "1: " TUSER(ldr) " %1,[%2],#0\n" \
267 "2:\n" \
268 " .pushsection .fixup,\"ax\"\n" \
269 " .align 2\n" \
270 "3: mov %0, %3\n" \
271 " mov %1, #0\n" \
272 " b 2b\n" \
273 " .popsection\n" \
274 " .pushsection __ex_table,\"a\"\n" \
275 " .align 3\n" \
276 " .long 1b, 3b\n" \
277 " .popsection" \
278 : "+r" (err), "=&r" (x) \
279 : "r" (addr), "i" (-EFAULT) \
280 : "cc")
281
282 #define __put_user(x,ptr) \
283 ({ \
284 long __pu_err = 0; \
285 __put_user_err((x),(ptr),__pu_err); \
286 __pu_err; \
287 })
288
289 #define __put_user_error(x,ptr,err) \
290 ({ \
291 __put_user_err((x),(ptr),err); \
292 (void) 0; \
293 })
294
295 #define __put_user_err(x,ptr,err) \
296 do { \
297 unsigned long __pu_addr = (unsigned long)(ptr); \
298 __typeof__(*(ptr)) __pu_val = (x); \
299 __chk_user_ptr(ptr); \
300 switch (sizeof(*(ptr))) { \
301 case 1: __put_user_asm_byte(__pu_val,__pu_addr,err); break; \
302 case 2: __put_user_asm_half(__pu_val,__pu_addr,err); break; \
303 case 4: __put_user_asm_word(__pu_val,__pu_addr,err); break; \
304 case 8: __put_user_asm_dword(__pu_val,__pu_addr,err); break; \
305 default: __put_user_bad(); \
306 } \
307 } while (0)
308
309 #define __put_user_asm_byte(x,__pu_addr,err) \
310 __asm__ __volatile__( \
311 "1: " TUSER(strb) " %1,[%2],#0\n" \
312 "2:\n" \
313 " .pushsection .fixup,\"ax\"\n" \
314 " .align 2\n" \
315 "3: mov %0, %3\n" \
316 " b 2b\n" \
317 " .popsection\n" \
318 " .pushsection __ex_table,\"a\"\n" \
319 " .align 3\n" \
320 " .long 1b, 3b\n" \
321 " .popsection" \
322 : "+r" (err) \
323 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
324 : "cc")
325
326 #ifndef __ARMEB__
327 #define __put_user_asm_half(x,__pu_addr,err) \
328 ({ \
329 unsigned long __temp = (unsigned long)(x); \
330 __put_user_asm_byte(__temp, __pu_addr, err); \
331 __put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
332 })
333 #else
334 #define __put_user_asm_half(x,__pu_addr,err) \
335 ({ \
336 unsigned long __temp = (unsigned long)(x); \
337 __put_user_asm_byte(__temp >> 8, __pu_addr, err); \
338 __put_user_asm_byte(__temp, __pu_addr + 1, err); \
339 })
340 #endif
341
342 #define __put_user_asm_word(x,__pu_addr,err) \
343 __asm__ __volatile__( \
344 "1: " TUSER(str) " %1,[%2],#0\n" \
345 "2:\n" \
346 " .pushsection .fixup,\"ax\"\n" \
347 " .align 2\n" \
348 "3: mov %0, %3\n" \
349 " b 2b\n" \
350 " .popsection\n" \
351 " .pushsection __ex_table,\"a\"\n" \
352 " .align 3\n" \
353 " .long 1b, 3b\n" \
354 " .popsection" \
355 : "+r" (err) \
356 : "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
357 : "cc")
358
359 #ifndef __ARMEB__
360 #define __reg_oper0 "%R2"
361 #define __reg_oper1 "%Q2"
362 #else
363 #define __reg_oper0 "%Q2"
364 #define __reg_oper1 "%R2"
365 #endif
366
367 #define __put_user_asm_dword(x,__pu_addr,err) \
368 __asm__ __volatile__( \
369 ARM( "1: " TUSER(str) " " __reg_oper1 ", [%1], #4\n" ) \
370 ARM( "2: " TUSER(str) " " __reg_oper0 ", [%1]\n" ) \
371 THUMB( "1: " TUSER(str) " " __reg_oper1 ", [%1]\n" ) \
372 THUMB( "2: " TUSER(str) " " __reg_oper0 ", [%1, #4]\n" ) \
373 "3:\n" \
374 " .pushsection .fixup,\"ax\"\n" \
375 " .align 2\n" \
376 "4: mov %0, %3\n" \
377 " b 3b\n" \
378 " .popsection\n" \
379 " .pushsection __ex_table,\"a\"\n" \
380 " .align 3\n" \
381 " .long 1b, 4b\n" \
382 " .long 2b, 4b\n" \
383 " .popsection" \
384 : "+r" (err), "+r" (__pu_addr) \
385 : "r" (x), "i" (-EFAULT) \
386 : "cc")
387
388
389 #ifdef CONFIG_MMU
390 extern unsigned long __must_check __copy_from_user(void *to, const void __user *from, unsigned long n);
391 extern unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n);
392 extern unsigned long __must_check __copy_to_user_std(void __user *to, const void *from, unsigned long n);
393 extern unsigned long __must_check __clear_user(void __user *addr, unsigned long n);
394 extern unsigned long __must_check __clear_user_std(void __user *addr, unsigned long n);
395 #else
396 #define __copy_from_user(to,from,n) (memcpy(to, (void __force *)from, n), 0)
397 #define __copy_to_user(to,from,n) (memcpy((void __force *)to, from, n), 0)
398 #define __clear_user(addr,n) (memset((void __force *)addr, 0, n), 0)
399 #endif
400
401 extern unsigned long __must_check __strncpy_from_user(char *to, const char __user *from, unsigned long count);
402 extern unsigned long __must_check __strnlen_user(const char __user *s, long n);
403
404 static inline unsigned long __must_check copy_from_user(void *to, const void __user *from, unsigned long n)
405 {
406 if (access_ok(VERIFY_READ, from, n))
407 n = __copy_from_user(to, from, n);
408 else /* security hole - plug it */
409 memset(to, 0, n);
410 return n;
411 }
412
413 static inline unsigned long __must_check copy_to_user(void __user *to, const void *from, unsigned long n)
414 {
415 if (access_ok(VERIFY_WRITE, to, n))
416 n = __copy_to_user(to, from, n);
417 return n;
418 }
419
420 #define __copy_to_user_inatomic __copy_to_user
421 #define __copy_from_user_inatomic __copy_from_user
422
423 static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
424 {
425 if (access_ok(VERIFY_WRITE, to, n))
426 n = __clear_user(to, n);
427 return n;
428 }
429
430 static inline long __must_check strncpy_from_user(char *dst, const char __user *src, long count)
431 {
432 long res = -EFAULT;
433 if (access_ok(VERIFY_READ, src, 1))
434 res = __strncpy_from_user(dst, src, count);
435 return res;
436 }
437
438 #define strlen_user(s) strnlen_user(s, ~0UL >> 1)
439
440 static inline long __must_check strnlen_user(const char __user *s, long n)
441 {
442 unsigned long res = 0;
443
444 if (__addr_ok(s))
445 res = __strnlen_user(s, n);
446
447 return res;
448 }
449
450 #endif /* _ASMARM_UACCESS_H */