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JFS: Add back directory i_size calculations for legacy partitions
[linux-2.6/kvm.git] / include / asm-sh / uaccess.h
blob2cb01861e7c550babe2e44409aa0be3942d2415a
1 /* $Id: uaccess.h,v 1.11 2003/10/13 07:21:20 lethal Exp $
2 *
3 * User space memory access functions
4 *
5 * Copyright (C) 1999, 2002 Niibe Yutaka
6 * Copyright (C) 2003 Paul Mundt
7 *
8 * Based on:
9 * MIPS implementation version 1.15 by
10 * Copyright (C) 1996, 1997, 1998 by Ralf Baechle
11 * and i386 version.
12 */
13 #ifndef __ASM_SH_UACCESS_H
14 #define __ASM_SH_UACCESS_H
15
16 #include <linux/errno.h>
17 #include <linux/sched.h>
18
19 /*
20 * NOTE: Macro/functions in this file depends on threads_info.h implementation.
21 * Assumes:
22 * TI_FLAGS == 8
23 * TIF_USERSPACE == 31
24 * USER_ADDR_LIMIT == 0x80000000
25 */
26
27 #define VERIFY_READ 0
28 #define VERIFY_WRITE 1
29
30 typedef struct {
31 unsigned int is_user_space;
32 } mm_segment_t;
33
34 /*
35 * The fs value determines whether argument validity checking should be
36 * performed or not. If get_fs() == USER_DS, checking is performed, with
37 * get_fs() == KERNEL_DS, checking is bypassed.
38 *
39 * For historical reasons (Data Segment Register?), these macros are misnamed.
40 */
41
42 #define MAKE_MM_SEG(s) ((mm_segment_t) { (s) })
43 #define segment_eq(a,b) ((a).is_user_space == (b).is_user_space)
44
45 #define USER_ADDR_LIMIT 0x80000000
46
47 #define KERNEL_DS MAKE_MM_SEG(0)
48 #define USER_DS MAKE_MM_SEG(1)
49
50 #define get_ds() (KERNEL_DS)
51
52 #if !defined(CONFIG_MMU)
53 static inline mm_segment_t get_fs(void)
54 {
55 return USER_DS;
56 }
57
58 static inline void set_fs(mm_segment_t s)
59 {
60 }
61
62 /*
63 * __access_ok: Check if address with size is OK or not.
64 *
65 * If we don't have an MMU (or if its disabled) the only thing we really have
66 * to look out for is if the address resides somewhere outside of what
67 * available RAM we have.
68 *
69 * TODO: This check could probably also stand to be restricted somewhat more..
70 * though it still does the Right Thing(tm) for the time being.
71 */
72 static inline int __access_ok(unsigned long addr, unsigned long size)
73 {
74 extern unsigned long memory_start, memory_end;
75
76 return ((addr >= memory_start) && ((addr + size) < memory_end));
77 }
78 #else /* CONFIG_MMU */
79 static inline mm_segment_t get_fs(void)
80 {
81 return MAKE_MM_SEG(test_thread_flag(TIF_USERSPACE));
82 }
83
84 static inline void set_fs(mm_segment_t s)
85 {
86 unsigned long ti, flag;
87 __asm__ __volatile__(
88 "stc r7_bank, %0\n\t"
89 "mov.l @(8,%0), %1\n\t"
90 "shal %1\n\t"
91 "cmp/pl %2\n\t"
92 "rotcr %1\n\t"
93 "mov.l %1, @(8,%0)"
94 : "=&r" (ti), "=&r" (flag)
95 : "r" (s.is_user_space)
96 : "t");
97 /****
98 if (s.is_user_space)
99 set_thread_flag(TIF_USERSPACE);
100 else
101 clear_thread_flag(TIF_USERSPACE);
102 ****/
103 }
104
105 /*
106 * __access_ok: Check if address with size is OK or not.
107 *
108 * We do three checks:
109 * (1) is it user space?
110 * (2) addr + size --> carry?
111 * (3) addr + size >= 0x80000000 (USER_ADDR_LIMIT)
112 *
113 * (1) (2) (3) | RESULT
114 * 0 0 0 | ok
115 * 0 0 1 | ok
116 * 0 1 0 | bad
117 * 0 1 1 | bad
118 * 1 0 0 | ok
119 * 1 0 1 | bad
120 * 1 1 0 | bad
121 * 1 1 1 | bad
122 */
123 static inline int __access_ok(unsigned long addr, unsigned long size)
124 {
125 unsigned long flag, tmp;
126
127 __asm__("stc r7_bank, %0\n\t"
128 "mov.l @(8,%0), %0\n\t"
129 "clrt\n\t"
130 "addc %2, %1\n\t"
131 "and %1, %0\n\t"
132 "rotcl %0\n\t"
133 "rotcl %0\n\t"
134 "and #3, %0"
135 : "=&z" (flag), "=r" (tmp)
136 : "r" (addr), "1" (size)
137 : "t");
138
139 return flag == 0;
140 }
141 #endif /* CONFIG_MMU */
142
143 static inline int access_ok(int type, const void __user *p, unsigned long size)
144 {
145 unsigned long addr = (unsigned long)p;
146 return __access_ok(addr, size);
147 }
148
149 /*
150 * Uh, these should become the main single-value transfer routines ...
151 * They automatically use the right size if we just have the right
152 * pointer type ...
153 *
154 * As SuperH uses the same address space for kernel and user data, we
155 * can just do these as direct assignments.
156 *
157 * Careful to not
158 * (a) re-use the arguments for side effects (sizeof is ok)
159 * (b) require any knowledge of processes at this stage
160 */
161 #define put_user(x,ptr) __put_user_check((x),(ptr),sizeof(*(ptr)))
162 #define get_user(x,ptr) __get_user_check((x),(ptr),sizeof(*(ptr)))
163
164 /*
165 * The "__xxx" versions do not do address space checking, useful when
166 * doing multiple accesses to the same area (the user has to do the
167 * checks by hand with "access_ok()")
168 */
169 #define __put_user(x,ptr) \
170 __put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
171 #define __get_user(x,ptr) \
172 __get_user_nocheck((x),(ptr),sizeof(*(ptr)))
173
174 struct __large_struct { unsigned long buf[100]; };
175 #define __m(x) (*(struct __large_struct *)(x))
176
177 #define __get_user_size(x,ptr,size,retval) \
178 do { \
179 retval = 0; \
180 switch (size) { \
181 case 1: \
182 __get_user_asm(x, ptr, retval, "b"); \
183 break; \
184 case 2: \
185 __get_user_asm(x, ptr, retval, "w"); \
186 break; \
187 case 4: \
188 __get_user_asm(x, ptr, retval, "l"); \
189 break; \
190 default: \
191 __get_user_unknown(); \
192 break; \
193 } \
194 } while (0)
195
196 #define __get_user_nocheck(x,ptr,size) \
197 ({ \
198 long __gu_err, __gu_val; \
199 __get_user_size(__gu_val, (ptr), (size), __gu_err); \
200 (x) = (__typeof__(*(ptr)))__gu_val; \
201 __gu_err; \
202 })
203
204 #define __get_user_check(x,ptr,size) \
205 ({ \
206 long __gu_err, __gu_val; \
207 switch (size) { \
208 case 1: \
209 __get_user_1(__gu_val, (ptr), __gu_err); \
210 break; \
211 case 2: \
212 __get_user_2(__gu_val, (ptr), __gu_err); \
213 break; \
214 case 4: \
215 __get_user_4(__gu_val, (ptr), __gu_err); \
216 break; \
217 default: \
218 __get_user_unknown(); \
219 break; \
220 } \
221 \
222 (x) = (__typeof__(*(ptr)))__gu_val; \
223 __gu_err; \
224 })
225
226 #define __get_user_1(x,addr,err) ({ \
227 __asm__("stc r7_bank, %1\n\t" \
228 "mov.l @(8,%1), %1\n\t" \
229 "and %2, %1\n\t" \
230 "cmp/pz %1\n\t" \
231 "bt/s 1f\n\t" \
232 " mov #0, %0\n\t" \
233 "0:\n" \
234 "mov #-14, %0\n\t" \
235 "bra 2f\n\t" \
236 " mov #0, %1\n" \
237 "1:\n\t" \
238 "mov.b @%2, %1\n\t" \
239 "extu.b %1, %1\n" \
240 "2:\n" \
241 ".section __ex_table,\"a\"\n\t" \
242 ".long 1b, 0b\n\t" \
243 ".previous" \
244 : "=&r" (err), "=&r" (x) \
245 : "r" (addr) \
246 : "t"); \
247 })
248
249 #define __get_user_2(x,addr,err) ({ \
250 __asm__("stc r7_bank, %1\n\t" \
251 "mov.l @(8,%1), %1\n\t" \
252 "and %2, %1\n\t" \
253 "cmp/pz %1\n\t" \
254 "bt/s 1f\n\t" \
255 " mov #0, %0\n\t" \
256 "0:\n" \
257 "mov #-14, %0\n\t" \
258 "bra 2f\n\t" \
259 " mov #0, %1\n" \
260 "1:\n\t" \
261 "mov.w @%2, %1\n\t" \
262 "extu.w %1, %1\n" \
263 "2:\n" \
264 ".section __ex_table,\"a\"\n\t" \
265 ".long 1b, 0b\n\t" \
266 ".previous" \
267 : "=&r" (err), "=&r" (x) \
268 : "r" (addr) \
269 : "t"); \
270 })
271
272 #define __get_user_4(x,addr,err) ({ \
273 __asm__("stc r7_bank, %1\n\t" \
274 "mov.l @(8,%1), %1\n\t" \
275 "and %2, %1\n\t" \
276 "cmp/pz %1\n\t" \
277 "bt/s 1f\n\t" \
278 " mov #0, %0\n\t" \
279 "0:\n" \
280 "mov #-14, %0\n\t" \
281 "bra 2f\n\t" \
282 " mov #0, %1\n" \
283 "1:\n\t" \
284 "mov.l @%2, %1\n\t" \
285 "2:\n" \
286 ".section __ex_table,\"a\"\n\t" \
287 ".long 1b, 0b\n\t" \
288 ".previous" \
289 : "=&r" (err), "=&r" (x) \
290 : "r" (addr) \
291 : "t"); \
292 })
293
294 #define __get_user_asm(x, addr, err, insn) \
295 ({ \
296 __asm__ __volatile__( \
297 "1:\n\t" \
298 "mov." insn " %2, %1\n\t" \
299 "mov #0, %0\n" \
300 "2:\n" \
301 ".section .fixup,\"ax\"\n" \
302 "3:\n\t" \
303 "mov #0, %1\n\t" \
304 "mov.l 4f, %0\n\t" \
305 "jmp @%0\n\t" \
306 " mov %3, %0\n" \
307 "4: .long 2b\n\t" \
308 ".previous\n" \
309 ".section __ex_table,\"a\"\n\t" \
310 ".long 1b, 3b\n\t" \
311 ".previous" \
312 :"=&r" (err), "=&r" (x) \
313 :"m" (__m(addr)), "i" (-EFAULT)); })
314
315 extern void __get_user_unknown(void);
316
317 #define __put_user_size(x,ptr,size,retval) \
318 do { \
319 retval = 0; \
320 switch (size) { \
321 case 1: \
322 __put_user_asm(x, ptr, retval, "b"); \
323 break; \
324 case 2: \
325 __put_user_asm(x, ptr, retval, "w"); \
326 break; \
327 case 4: \
328 __put_user_asm(x, ptr, retval, "l"); \
329 break; \
330 case 8: \
331 __put_user_u64(x, ptr, retval); \
332 break; \
333 default: \
334 __put_user_unknown(); \
335 } \
336 } while (0)
337
338 #define __put_user_nocheck(x,ptr,size) \
339 ({ \
340 long __pu_err; \
341 __put_user_size((x),(ptr),(size),__pu_err); \
342 __pu_err; \
343 })
344
345 #define __put_user_check(x,ptr,size) \
346 ({ \
347 long __pu_err = -EFAULT; \
348 __typeof__(*(ptr)) *__pu_addr = (ptr); \
349 \
350 if (__access_ok((unsigned long)__pu_addr,size)) \
351 __put_user_size((x),__pu_addr,(size),__pu_err); \
352 __pu_err; \
353 })
354
355 #define __put_user_asm(x, addr, err, insn) \
356 ({ \
357 __asm__ __volatile__( \
358 "1:\n\t" \
359 "mov." insn " %1, %2\n\t" \
360 "mov #0, %0\n" \
361 "2:\n" \
362 ".section .fixup,\"ax\"\n" \
363 "3:\n\t" \
364 "nop\n\t" \
365 "mov.l 4f, %0\n\t" \
366 "jmp @%0\n\t" \
367 "mov %3, %0\n" \
368 "4: .long 2b\n\t" \
369 ".previous\n" \
370 ".section __ex_table,\"a\"\n\t" \
371 ".long 1b, 3b\n\t" \
372 ".previous" \
373 :"=&r" (err) \
374 :"r" (x), "m" (__m(addr)), "i" (-EFAULT) \
375 :"memory"); })
376
377 #if defined(__LITTLE_ENDIAN__)
378 #define __put_user_u64(val,addr,retval) \
379 ({ \
380 __asm__ __volatile__( \
381 "1:\n\t" \
382 "mov.l %R1,%2\n\t" \
383 "mov.l %S1,%T2\n\t" \
384 "mov #0,%0\n" \
385 "2:\n" \
386 ".section .fixup,\"ax\"\n" \
387 "3:\n\t" \
388 "nop\n\t" \
389 "mov.l 4f,%0\n\t" \
390 "jmp @%0\n\t" \
391 " mov %3,%0\n" \
392 "4: .long 2b\n\t" \
393 ".previous\n" \
394 ".section __ex_table,\"a\"\n\t" \
395 ".long 1b, 3b\n\t" \
396 ".previous" \
397 : "=r" (retval) \
398 : "r" (val), "m" (__m(addr)), "i" (-EFAULT) \
399 : "memory"); })
400 #else
401 #define __put_user_u64(val,addr,retval) \
402 ({ \
403 __asm__ __volatile__( \
404 "1:\n\t" \
405 "mov.l %S1,%2\n\t" \
406 "mov.l %R1,%T2\n\t" \
407 "mov #0,%0\n" \
408 "2:\n" \
409 ".section .fixup,\"ax\"\n" \
410 "3:\n\t" \
411 "nop\n\t" \
412 "mov.l 4f,%0\n\t" \
413 "jmp @%0\n\t" \
414 " mov %3,%0\n" \
415 "4: .long 2b\n\t" \
416 ".previous\n" \
417 ".section __ex_table,\"a\"\n\t" \
418 ".long 1b, 3b\n\t" \
419 ".previous" \
420 : "=r" (retval) \
421 : "r" (val), "m" (__m(addr)), "i" (-EFAULT) \
422 : "memory"); })
423 #endif
424
425 extern void __put_user_unknown(void);
426 \f
427 /* Generic arbitrary sized copy. */
428 /* Return the number of bytes NOT copied */
429 extern __kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n);
430
431 #define copy_to_user(to,from,n) ({ \
432 void *__copy_to = (void *) (to); \
433 __kernel_size_t __copy_size = (__kernel_size_t) (n); \
434 __kernel_size_t __copy_res; \
435 if(__copy_size && __access_ok((unsigned long)__copy_to, __copy_size)) { \
436 __copy_res = __copy_user(__copy_to, (void *) (from), __copy_size); \
437 } else __copy_res = __copy_size; \
438 __copy_res; })
439
440 #define __copy_to_user(to,from,n) \
441 __copy_user((void *)(to), \
442 (void *)(from), n)
443
444 #define __copy_to_user_inatomic __copy_to_user
445 #define __copy_from_user_inatomic __copy_from_user
446
447
448 #define copy_from_user(to,from,n) ({ \
449 void *__copy_to = (void *) (to); \
450 void *__copy_from = (void *) (from); \
451 __kernel_size_t __copy_size = (__kernel_size_t) (n); \
452 __kernel_size_t __copy_res; \
453 if(__copy_size && __access_ok((unsigned long)__copy_from, __copy_size)) { \
454 __copy_res = __copy_user(__copy_to, __copy_from, __copy_size); \
455 } else __copy_res = __copy_size; \
456 __copy_res; })
457
458 #define __copy_from_user(to,from,n) \
459 __copy_user((void *)(to), \
460 (void *)(from), n)
461
462 /*
463 * Clear the area and return remaining number of bytes
464 * (on failure. Usually it's 0.)
465 */
466 extern __kernel_size_t __clear_user(void *addr, __kernel_size_t size);
467
468 #define clear_user(addr,n) ({ \
469 void * __cl_addr = (addr); \
470 unsigned long __cl_size = (n); \
471 if (__cl_size && __access_ok(((unsigned long)(__cl_addr)), __cl_size)) \
472 __cl_size = __clear_user(__cl_addr, __cl_size); \
473 __cl_size; })
474
475 static __inline__ int
476 __strncpy_from_user(unsigned long __dest, unsigned long __user __src, int __count)
477 {
478 __kernel_size_t res;
479 unsigned long __dummy, _d, _s;
480
481 __asm__ __volatile__(
482 "9:\n"
483 "mov.b @%2+, %1\n\t"
484 "cmp/eq #0, %1\n\t"
485 "bt/s 2f\n"
486 "1:\n"
487 "mov.b %1, @%3\n\t"
488 "dt %7\n\t"
489 "bf/s 9b\n\t"
490 " add #1, %3\n\t"
491 "2:\n\t"
492 "sub %7, %0\n"
493 "3:\n"
494 ".section .fixup,\"ax\"\n"
495 "4:\n\t"
496 "mov.l 5f, %1\n\t"
497 "jmp @%1\n\t"
498 " mov %8, %0\n\t"
499 ".balign 4\n"
500 "5: .long 3b\n"
501 ".previous\n"
502 ".section __ex_table,\"a\"\n"
503 " .balign 4\n"
504 " .long 9b,4b\n"
505 ".previous"
506 : "=r" (res), "=&z" (__dummy), "=r" (_s), "=r" (_d)
507 : "0" (__count), "2" (__src), "3" (__dest), "r" (__count),
508 "i" (-EFAULT)
509 : "memory", "t");
510
511 return res;
512 }
513
514 #define strncpy_from_user(dest,src,count) ({ \
515 unsigned long __sfu_src = (unsigned long) (src); \
516 int __sfu_count = (int) (count); \
517 long __sfu_res = -EFAULT; \
518 if(__access_ok(__sfu_src, __sfu_count)) { \
519 __sfu_res = __strncpy_from_user((unsigned long) (dest), __sfu_src, __sfu_count); \
520 } __sfu_res; })
521
522 /*
523 * Return the size of a string (including the ending 0!)
524 */
525 static __inline__ long __strnlen_user(const char __user *__s, long __n)
526 {
527 unsigned long res;
528 unsigned long __dummy;
529
530 __asm__ __volatile__(
531 "9:\n"
532 "cmp/eq %4, %0\n\t"
533 "bt 2f\n"
534 "1:\t"
535 "mov.b @(%0,%3), %1\n\t"
536 "tst %1, %1\n\t"
537 "bf/s 9b\n\t"
538 " add #1, %0\n"
539 "2:\n"
540 ".section .fixup,\"ax\"\n"
541 "3:\n\t"
542 "mov.l 4f, %1\n\t"
543 "jmp @%1\n\t"
544 " mov %5, %0\n"
545 ".balign 4\n"
546 "4: .long 2b\n"
547 ".previous\n"
548 ".section __ex_table,\"a\"\n"
549 " .balign 4\n"
550 " .long 1b,3b\n"
551 ".previous"
552 : "=z" (res), "=&r" (__dummy)
553 : "0" (0), "r" (__s), "r" (__n), "i" (-EFAULT)
554 : "t");
555 return res;
556 }
557
558 static __inline__ long strnlen_user(const char __user *s, long n)
559 {
560 if (!access_ok(VERIFY_READ, s, n))
561 return 0;
562 else
563 return __strnlen_user(s, n);
564 }
565
566 static __inline__ long strlen_user(const char __user *s)
567 {
568 if (!access_ok(VERIFY_READ, s, 0))
569 return 0;
570 else
571 return __strnlen_user(s, ~0UL >> 1);
572 }
573
574 /*
575 * The exception table consists of pairs of addresses: the first is the
576 * address of an instruction that is allowed to fault, and the second is
577 * the address at which the program should continue. No registers are
578 * modified, so it is entirely up to the continuation code to figure out
579 * what to do.
580 *
581 * All the routines below use bits of fixup code that are out of line
582 * with the main instruction path. This means when everything is well,
583 * we don't even have to jump over them. Further, they do not intrude
584 * on our cache or tlb entries.
585 */
586
587 struct exception_table_entry
588 {
589 unsigned long insn, fixup;
590 };
591
592 extern int fixup_exception(struct pt_regs *regs);
593
594 #endif /* __ASM_SH_UACCESS_H */
kernel-based virtual machine