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b920de1b DH |
1 | /* MN10300 userspace access functions |
2 | * | |
3 | * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved. | |
4 | * Written by David Howells (dhowells@redhat.com) | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or | |
7 | * modify it under the terms of the GNU General Public Licence | |
8 | * as published by the Free Software Foundation; either version | |
9 | * 2 of the Licence, or (at your option) any later version. | |
10 | */ | |
11 | #ifndef _ASM_UACCESS_H | |
12 | #define _ASM_UACCESS_H | |
13 | ||
14 | /* | |
15 | * User space memory access functions | |
16 | */ | |
7c7fcf76 | 17 | #include <linux/thread_info.h> |
35052cff | 18 | #include <linux/kernel.h> |
b920de1b | 19 | #include <asm/page.h> |
b920de1b DH |
20 | #include <asm/errno.h> |
21 | ||
22 | #define VERIFY_READ 0 | |
23 | #define VERIFY_WRITE 1 | |
24 | ||
25 | /* | |
26 | * The fs value determines whether argument validity checking should be | |
27 | * performed or not. If get_fs() == USER_DS, checking is performed, with | |
28 | * get_fs() == KERNEL_DS, checking is bypassed. | |
29 | * | |
30 | * For historical reasons, these macros are grossly misnamed. | |
31 | */ | |
b920de1b DH |
32 | #define MAKE_MM_SEG(s) ((mm_segment_t) { (s) }) |
33 | ||
34 | #define KERNEL_XDS MAKE_MM_SEG(0xBFFFFFFF) | |
35 | #define KERNEL_DS MAKE_MM_SEG(0x9FFFFFFF) | |
36 | #define USER_DS MAKE_MM_SEG(TASK_SIZE) | |
37 | ||
38 | #define get_ds() (KERNEL_DS) | |
39 | #define get_fs() (current_thread_info()->addr_limit) | |
40 | #define set_fs(x) (current_thread_info()->addr_limit = (x)) | |
41 | #define __kernel_ds_p() (current_thread_info()->addr_limit.seg == 0x9FFFFFFF) | |
42 | ||
43 | #define segment_eq(a, b) ((a).seg == (b).seg) | |
44 | ||
45 | #define __addr_ok(addr) \ | |
46 | ((unsigned long)(addr) < (current_thread_info()->addr_limit.seg)) | |
47 | ||
48 | /* | |
49 | * check that a range of addresses falls within the current address limit | |
50 | */ | |
51 | static inline int ___range_ok(unsigned long addr, unsigned int size) | |
52 | { | |
53 | int flag = 1, tmp; | |
54 | ||
55 | asm(" add %3,%1 \n" /* set C-flag if addr + size > 4Gb */ | |
56 | " bcs 0f \n" | |
57 | " cmp %4,%1 \n" /* jump if addr+size>limit (error) */ | |
58 | " bhi 0f \n" | |
59 | " clr %0 \n" /* mark okay */ | |
60 | "0: \n" | |
61 | : "=r"(flag), "=&r"(tmp) | |
62 | : "1"(addr), "ir"(size), | |
63 | "r"(current_thread_info()->addr_limit.seg), "0"(flag) | |
64 | : "cc" | |
65 | ); | |
66 | ||
67 | return flag; | |
68 | } | |
69 | ||
70 | #define __range_ok(addr, size) ___range_ok((unsigned long)(addr), (u32)(size)) | |
71 | ||
72 | #define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0) | |
73 | #define __access_ok(addr, size) (__range_ok((addr), (size)) == 0) | |
74 | ||
75 | static inline int verify_area(int type, const void *addr, unsigned long size) | |
76 | { | |
77 | return access_ok(type, addr, size) ? 0 : -EFAULT; | |
78 | } | |
79 | ||
80 | ||
81 | /* | |
82 | * The exception table consists of pairs of addresses: the first is the | |
83 | * address of an instruction that is allowed to fault, and the second is | |
84 | * the address at which the program should continue. No registers are | |
85 | * modified, so it is entirely up to the continuation code to figure out | |
86 | * what to do. | |
87 | * | |
88 | * All the routines below use bits of fixup code that are out of line | |
89 | * with the main instruction path. This means when everything is well, | |
90 | * we don't even have to jump over them. Further, they do not intrude | |
91 | * on our cache or tlb entries. | |
92 | */ | |
93 | ||
94 | struct exception_table_entry | |
95 | { | |
96 | unsigned long insn, fixup; | |
97 | }; | |
98 | ||
99 | /* Returns 0 if exception not found and fixup otherwise. */ | |
100 | extern int fixup_exception(struct pt_regs *regs); | |
101 | ||
102 | #define put_user(x, ptr) __put_user_check((x), (ptr), sizeof(*(ptr))) | |
103 | #define get_user(x, ptr) __get_user_check((x), (ptr), sizeof(*(ptr))) | |
104 | ||
105 | /* | |
106 | * The "__xxx" versions do not do address space checking, useful when | |
107 | * doing multiple accesses to the same area (the user has to do the | |
108 | * checks by hand with "access_ok()") | |
109 | */ | |
110 | #define __put_user(x, ptr) __put_user_nocheck((x), (ptr), sizeof(*(ptr))) | |
111 | #define __get_user(x, ptr) __get_user_nocheck((x), (ptr), sizeof(*(ptr))) | |
112 | ||
113 | /* | |
114 | * The "xxx_ret" versions return constant specified in third argument, if | |
115 | * something bad happens. These macros can be optimized for the | |
116 | * case of just returning from the function xxx_ret is used. | |
117 | */ | |
118 | ||
119 | #define put_user_ret(x, ptr, ret) \ | |
120 | ({ if (put_user((x), (ptr))) return (ret); }) | |
121 | #define get_user_ret(x, ptr, ret) \ | |
122 | ({ if (get_user((x), (ptr))) return (ret); }) | |
123 | #define __put_user_ret(x, ptr, ret) \ | |
124 | ({ if (__put_user((x), (ptr))) return (ret); }) | |
125 | #define __get_user_ret(x, ptr, ret) \ | |
126 | ({ if (__get_user((x), (ptr))) return (ret); }) | |
127 | ||
128 | struct __large_struct { unsigned long buf[100]; }; | |
129 | #define __m(x) (*(struct __large_struct *)(x)) | |
130 | ||
d22a001b MS |
131 | #define __get_user_nocheck(x, ptr, size) \ |
132 | ({ \ | |
133 | unsigned long __gu_addr; \ | |
134 | int __gu_err; \ | |
135 | __gu_addr = (unsigned long) (ptr); \ | |
136 | switch (size) { \ | |
137 | case 1: { \ | |
138 | unsigned char __gu_val; \ | |
139 | __get_user_asm("bu"); \ | |
140 | (x) = *(__force __typeof__(*(ptr))*) &__gu_val; \ | |
141 | break; \ | |
142 | } \ | |
143 | case 2: { \ | |
144 | unsigned short __gu_val; \ | |
145 | __get_user_asm("hu"); \ | |
146 | (x) = *(__force __typeof__(*(ptr))*) &__gu_val; \ | |
147 | break; \ | |
148 | } \ | |
149 | case 4: { \ | |
150 | unsigned int __gu_val; \ | |
151 | __get_user_asm(""); \ | |
152 | (x) = *(__force __typeof__(*(ptr))*) &__gu_val; \ | |
153 | break; \ | |
154 | } \ | |
155 | default: \ | |
156 | __get_user_unknown(); \ | |
157 | break; \ | |
158 | } \ | |
159 | __gu_err; \ | |
b920de1b DH |
160 | }) |
161 | ||
d22a001b MS |
162 | #define __get_user_check(x, ptr, size) \ |
163 | ({ \ | |
c6dc9f0a | 164 | const __typeof__(*(ptr))* __guc_ptr = (ptr); \ |
d22a001b | 165 | int _e; \ |
6fc34436 TK |
166 | if (likely(__access_ok((unsigned long) __guc_ptr, (size)))) \ |
167 | _e = __get_user_nocheck((x), __guc_ptr, (size)); \ | |
d22a001b MS |
168 | else { \ |
169 | _e = -EFAULT; \ | |
170 | (x) = (__typeof__(x))0; \ | |
171 | } \ | |
172 | _e; \ | |
b920de1b DH |
173 | }) |
174 | ||
175 | #define __get_user_asm(INSN) \ | |
176 | ({ \ | |
177 | asm volatile( \ | |
178 | "1:\n" \ | |
179 | " mov"INSN" %2,%1\n" \ | |
180 | " mov 0,%0\n" \ | |
181 | "2:\n" \ | |
182 | " .section .fixup,\"ax\"\n" \ | |
183 | "3:\n\t" \ | |
184 | " mov %3,%0\n" \ | |
185 | " jmp 2b\n" \ | |
186 | " .previous\n" \ | |
187 | " .section __ex_table,\"a\"\n" \ | |
188 | " .balign 4\n" \ | |
189 | " .long 1b, 3b\n" \ | |
190 | " .previous" \ | |
191 | : "=&r" (__gu_err), "=&r" (__gu_val) \ | |
192 | : "m" (__m(__gu_addr)), "i" (-EFAULT)); \ | |
193 | }) | |
194 | ||
195 | extern int __get_user_unknown(void); | |
196 | ||
197 | #define __put_user_nocheck(x, ptr, size) \ | |
198 | ({ \ | |
199 | union { \ | |
200 | __typeof__(*(ptr)) val; \ | |
201 | u32 bits[2]; \ | |
202 | } __pu_val; \ | |
203 | unsigned long __pu_addr; \ | |
204 | int __pu_err; \ | |
205 | __pu_val.val = (x); \ | |
206 | __pu_addr = (unsigned long) (ptr); \ | |
207 | switch (size) { \ | |
208 | case 1: __put_user_asm("bu"); break; \ | |
209 | case 2: __put_user_asm("hu"); break; \ | |
210 | case 4: __put_user_asm("" ); break; \ | |
211 | case 8: __put_user_asm8(); break; \ | |
212 | default: __pu_err = __put_user_unknown(); break; \ | |
213 | } \ | |
214 | __pu_err; \ | |
215 | }) | |
216 | ||
217 | #define __put_user_check(x, ptr, size) \ | |
218 | ({ \ | |
219 | union { \ | |
220 | __typeof__(*(ptr)) val; \ | |
221 | u32 bits[2]; \ | |
222 | } __pu_val; \ | |
223 | unsigned long __pu_addr; \ | |
224 | int __pu_err; \ | |
225 | __pu_val.val = (x); \ | |
226 | __pu_addr = (unsigned long) (ptr); \ | |
227 | if (likely(__access_ok(__pu_addr, size))) { \ | |
228 | switch (size) { \ | |
229 | case 1: __put_user_asm("bu"); break; \ | |
230 | case 2: __put_user_asm("hu"); break; \ | |
231 | case 4: __put_user_asm("" ); break; \ | |
232 | case 8: __put_user_asm8(); break; \ | |
233 | default: __pu_err = __put_user_unknown(); break; \ | |
234 | } \ | |
235 | } \ | |
236 | else { \ | |
237 | __pu_err = -EFAULT; \ | |
238 | } \ | |
239 | __pu_err; \ | |
240 | }) | |
241 | ||
242 | #define __put_user_asm(INSN) \ | |
243 | ({ \ | |
244 | asm volatile( \ | |
245 | "1:\n" \ | |
246 | " mov"INSN" %1,%2\n" \ | |
247 | " mov 0,%0\n" \ | |
248 | "2:\n" \ | |
249 | " .section .fixup,\"ax\"\n" \ | |
250 | "3:\n" \ | |
251 | " mov %3,%0\n" \ | |
252 | " jmp 2b\n" \ | |
253 | " .previous\n" \ | |
254 | " .section __ex_table,\"a\"\n" \ | |
255 | " .balign 4\n" \ | |
256 | " .long 1b, 3b\n" \ | |
257 | " .previous" \ | |
258 | : "=&r" (__pu_err) \ | |
259 | : "r" (__pu_val.val), "m" (__m(__pu_addr)), \ | |
260 | "i" (-EFAULT) \ | |
261 | ); \ | |
262 | }) | |
263 | ||
264 | #define __put_user_asm8() \ | |
265 | ({ \ | |
266 | asm volatile( \ | |
267 | "1: mov %1,%3 \n" \ | |
268 | "2: mov %2,%4 \n" \ | |
269 | " mov 0,%0 \n" \ | |
270 | "3: \n" \ | |
271 | " .section .fixup,\"ax\" \n" \ | |
272 | "4: \n" \ | |
273 | " mov %5,%0 \n" \ | |
54b71fba | 274 | " jmp 3b \n" \ |
b920de1b DH |
275 | " .previous \n" \ |
276 | " .section __ex_table,\"a\"\n" \ | |
277 | " .balign 4 \n" \ | |
278 | " .long 1b, 4b \n" \ | |
279 | " .long 2b, 4b \n" \ | |
280 | " .previous \n" \ | |
281 | : "=&r" (__pu_err) \ | |
282 | : "r" (__pu_val.bits[0]), "r" (__pu_val.bits[1]), \ | |
283 | "m" (__m(__pu_addr)), "m" (__m(__pu_addr+4)), \ | |
284 | "i" (-EFAULT) \ | |
285 | ); \ | |
286 | }) | |
287 | ||
288 | extern int __put_user_unknown(void); | |
289 | ||
290 | ||
291 | /* | |
292 | * Copy To/From Userspace | |
293 | */ | |
294 | /* Generic arbitrary sized copy. */ | |
295 | #define __copy_user(to, from, size) \ | |
296 | do { \ | |
297 | if (size) { \ | |
298 | void *__to = to; \ | |
299 | const void *__from = from; \ | |
300 | int w; \ | |
301 | asm volatile( \ | |
302 | "0: movbu (%0),%3;\n" \ | |
303 | "1: movbu %3,(%1);\n" \ | |
304 | " inc %0;\n" \ | |
305 | " inc %1;\n" \ | |
306 | " add -1,%2;\n" \ | |
307 | " bne 0b;\n" \ | |
308 | "2:\n" \ | |
309 | " .section .fixup,\"ax\"\n" \ | |
310 | "3: jmp 2b\n" \ | |
311 | " .previous\n" \ | |
312 | " .section __ex_table,\"a\"\n" \ | |
313 | " .balign 4\n" \ | |
314 | " .long 0b,3b\n" \ | |
315 | " .long 1b,3b\n" \ | |
316 | " .previous\n" \ | |
317 | : "=a"(__from), "=a"(__to), "=r"(size), "=&r"(w)\ | |
318 | : "0"(__from), "1"(__to), "2"(size) \ | |
d6bb7a1a | 319 | : "cc", "memory"); \ |
b920de1b DH |
320 | } \ |
321 | } while (0) | |
322 | ||
323 | #define __copy_user_zeroing(to, from, size) \ | |
324 | do { \ | |
325 | if (size) { \ | |
326 | void *__to = to; \ | |
327 | const void *__from = from; \ | |
328 | int w; \ | |
329 | asm volatile( \ | |
330 | "0: movbu (%0),%3;\n" \ | |
331 | "1: movbu %3,(%1);\n" \ | |
332 | " inc %0;\n" \ | |
333 | " inc %1;\n" \ | |
334 | " add -1,%2;\n" \ | |
335 | " bne 0b;\n" \ | |
336 | "2:\n" \ | |
337 | " .section .fixup,\"ax\"\n" \ | |
338 | "3:\n" \ | |
339 | " mov %2,%0\n" \ | |
340 | " clr %3\n" \ | |
341 | "4: movbu %3,(%1);\n" \ | |
342 | " inc %1;\n" \ | |
343 | " add -1,%2;\n" \ | |
344 | " bne 4b;\n" \ | |
345 | " mov %0,%2\n" \ | |
346 | " jmp 2b\n" \ | |
347 | " .previous\n" \ | |
348 | " .section __ex_table,\"a\"\n" \ | |
349 | " .balign 4\n" \ | |
350 | " .long 0b,3b\n" \ | |
351 | " .long 1b,3b\n" \ | |
352 | " .previous\n" \ | |
353 | : "=a"(__from), "=a"(__to), "=r"(size), "=&r"(w)\ | |
354 | : "0"(__from), "1"(__to), "2"(size) \ | |
d6bb7a1a | 355 | : "cc", "memory"); \ |
b920de1b DH |
356 | } \ |
357 | } while (0) | |
358 | ||
359 | /* We let the __ versions of copy_from/to_user inline, because they're often | |
360 | * used in fast paths and have only a small space overhead. | |
361 | */ | |
362 | static inline | |
363 | unsigned long __generic_copy_from_user_nocheck(void *to, const void *from, | |
364 | unsigned long n) | |
365 | { | |
366 | __copy_user_zeroing(to, from, n); | |
367 | return n; | |
368 | } | |
369 | ||
370 | static inline | |
371 | unsigned long __generic_copy_to_user_nocheck(void *to, const void *from, | |
372 | unsigned long n) | |
373 | { | |
374 | __copy_user(to, from, n); | |
375 | return n; | |
376 | } | |
377 | ||
378 | ||
379 | #if 0 | |
368dd5ac | 380 | #error "don't use - these macros don't increment to & from pointers" |
b920de1b DH |
381 | /* Optimize just a little bit when we know the size of the move. */ |
382 | #define __constant_copy_user(to, from, size) \ | |
383 | do { \ | |
384 | asm volatile( \ | |
385 | " mov %0,a0;\n" \ | |
386 | "0: movbu (%1),d3;\n" \ | |
387 | "1: movbu d3,(%2);\n" \ | |
388 | " add -1,a0;\n" \ | |
389 | " bne 0b;\n" \ | |
390 | "2:;" \ | |
391 | ".section .fixup,\"ax\"\n" \ | |
392 | "3: jmp 2b\n" \ | |
393 | ".previous\n" \ | |
394 | ".section __ex_table,\"a\"\n" \ | |
395 | " .balign 4\n" \ | |
396 | " .long 0b,3b\n" \ | |
397 | " .long 1b,3b\n" \ | |
398 | ".previous" \ | |
399 | : \ | |
400 | : "d"(size), "d"(to), "d"(from) \ | |
401 | : "d3", "a0"); \ | |
402 | } while (0) | |
403 | ||
404 | /* Optimize just a little bit when we know the size of the move. */ | |
405 | #define __constant_copy_user_zeroing(to, from, size) \ | |
406 | do { \ | |
407 | asm volatile( \ | |
408 | " mov %0,a0;\n" \ | |
409 | "0: movbu (%1),d3;\n" \ | |
410 | "1: movbu d3,(%2);\n" \ | |
411 | " add -1,a0;\n" \ | |
412 | " bne 0b;\n" \ | |
413 | "2:;" \ | |
414 | ".section .fixup,\"ax\"\n" \ | |
415 | "3: jmp 2b\n" \ | |
416 | ".previous\n" \ | |
417 | ".section __ex_table,\"a\"\n" \ | |
418 | " .balign 4\n" \ | |
419 | " .long 0b,3b\n" \ | |
420 | " .long 1b,3b\n" \ | |
421 | ".previous" \ | |
422 | : \ | |
423 | : "d"(size), "d"(to), "d"(from) \ | |
424 | : "d3", "a0"); \ | |
425 | } while (0) | |
426 | ||
427 | static inline | |
428 | unsigned long __constant_copy_to_user(void *to, const void *from, | |
429 | unsigned long n) | |
430 | { | |
431 | if (access_ok(VERIFY_WRITE, to, n)) | |
432 | __constant_copy_user(to, from, n); | |
433 | return n; | |
434 | } | |
435 | ||
436 | static inline | |
437 | unsigned long __constant_copy_from_user(void *to, const void *from, | |
438 | unsigned long n) | |
439 | { | |
440 | if (access_ok(VERIFY_READ, from, n)) | |
441 | __constant_copy_user_zeroing(to, from, n); | |
442 | return n; | |
443 | } | |
444 | ||
445 | static inline | |
446 | unsigned long __constant_copy_to_user_nocheck(void *to, const void *from, | |
447 | unsigned long n) | |
448 | { | |
449 | __constant_copy_user(to, from, n); | |
450 | return n; | |
451 | } | |
452 | ||
453 | static inline | |
454 | unsigned long __constant_copy_from_user_nocheck(void *to, const void *from, | |
455 | unsigned long n) | |
456 | { | |
457 | __constant_copy_user_zeroing(to, from, n); | |
458 | return n; | |
459 | } | |
460 | #endif | |
461 | ||
462 | extern unsigned long __generic_copy_to_user(void __user *, const void *, | |
463 | unsigned long); | |
464 | extern unsigned long __generic_copy_from_user(void *, const void __user *, | |
465 | unsigned long); | |
466 | ||
467 | #define __copy_to_user_inatomic(to, from, n) \ | |
468 | __generic_copy_to_user_nocheck((to), (from), (n)) | |
469 | #define __copy_from_user_inatomic(to, from, n) \ | |
470 | __generic_copy_from_user_nocheck((to), (from), (n)) | |
471 | ||
472 | #define __copy_to_user(to, from, n) \ | |
473 | ({ \ | |
3837a3cf | 474 | might_fault(); \ |
b920de1b DH |
475 | __copy_to_user_inatomic((to), (from), (n)); \ |
476 | }) | |
477 | ||
478 | #define __copy_from_user(to, from, n) \ | |
479 | ({ \ | |
3837a3cf | 480 | might_fault(); \ |
b920de1b DH |
481 | __copy_from_user_inatomic((to), (from), (n)); \ |
482 | }) | |
483 | ||
484 | ||
485 | #define copy_to_user(to, from, n) __generic_copy_to_user((to), (from), (n)) | |
486 | #define copy_from_user(to, from, n) __generic_copy_from_user((to), (from), (n)) | |
487 | ||
488 | extern long strncpy_from_user(char *dst, const char __user *src, long count); | |
489 | extern long __strncpy_from_user(char *dst, const char __user *src, long count); | |
490 | extern long strnlen_user(const char __user *str, long n); | |
491 | #define strlen_user(str) strnlen_user(str, ~0UL >> 1) | |
492 | extern unsigned long clear_user(void __user *mem, unsigned long len); | |
493 | extern unsigned long __clear_user(void __user *mem, unsigned long len); | |
494 | ||
495 | #endif /* _ASM_UACCESS_H */ |