summaryrefslogtreecommitdiffstats
path: root/include/asm-sh/uaccess.h
blob: 77c391fa93d6380b1f25996a692dc77ca5af66dc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
/* $Id: uaccess.h,v 1.11 2003/10/13 07:21:20 lethal Exp $
 *
 * User space memory access functions
 *
 * Copyright (C) 1999, 2002  Niibe Yutaka
 * Copyright (C) 2003  Paul Mundt
 *
 *  Based on:
 *     MIPS implementation version 1.15 by
 *              Copyright (C) 1996, 1997, 1998 by Ralf Baechle
 *     and i386 version.
 */
#ifndef __ASM_SH_UACCESS_H
#define __ASM_SH_UACCESS_H

#include <linux/errno.h>
#include <linux/sched.h>

#define VERIFY_READ    0
#define VERIFY_WRITE   1

/*
 * The fs value determines whether argument validity checking should be
 * performed or not.  If get_fs() == USER_DS, checking is performed, with
 * get_fs() == KERNEL_DS, checking is bypassed.
 *
 * For historical reasons (Data Segment Register?), these macros are misnamed.
 */

#define MAKE_MM_SEG(s)	((mm_segment_t) { (s) })

#define KERNEL_DS	MAKE_MM_SEG(0xFFFFFFFFUL)
#define USER_DS		MAKE_MM_SEG(PAGE_OFFSET)

#define segment_eq(a,b)	((a).seg == (b).seg)

#define get_ds()	(KERNEL_DS)

#if !defined(CONFIG_MMU)
/* NOMMU is always true */
#define __addr_ok(addr) (1)

static inline mm_segment_t get_fs(void)
{
	return USER_DS;
}

static inline void set_fs(mm_segment_t s)
{
}

/*
 * __access_ok: Check if address with size is OK or not.
 *
 * If we don't have an MMU (or if its disabled) the only thing we really have
 * to look out for is if the address resides somewhere outside of what
 * available RAM we have.
 *
 * TODO: This check could probably also stand to be restricted somewhat more..
 * though it still does the Right Thing(tm) for the time being.
 */
static inline int __access_ok(unsigned long addr, unsigned long size)
{
	return ((addr >= memory_start) && ((addr + size) < memory_end));
}
#else /* CONFIG_MMU */
#define __addr_ok(addr) \
	((unsigned long)(addr) < (current_thread_info()->addr_limit.seg))

#define get_fs()	(current_thread_info()->addr_limit)
#define set_fs(x)	(current_thread_info()->addr_limit = (x))

/*
 * __access_ok: Check if address with size is OK or not.
 *
 * Uhhuh, this needs 33-bit arithmetic. We have a carry..
 *
 * sum := addr + size;  carry? --> flag = true;
 * if (sum >= addr_limit) flag = true;
 */
static inline int __access_ok(unsigned long addr, unsigned long size)
{
	unsigned long flag, sum;

	__asm__("clrt\n\t"
		"addc	%3, %1\n\t"
		"movt	%0\n\t"
		"cmp/hi	%4, %1\n\t"
		"rotcl	%0"
		:"=&r" (flag), "=r" (sum)
		:"1" (addr), "r" (size),
		 "r" (current_thread_info()->addr_limit.seg)
		:"t");
	return flag == 0;

}
#endif /* CONFIG_MMU */

static inline int access_ok(int type, const void __user *p, unsigned long size)
{
	unsigned long addr = (unsigned long)p;
	return __access_ok(addr, size);
}

/*
 * Uh, these should become the main single-value transfer routines ...
 * They automatically use the right size if we just have the right
 * pointer type ...
 *
 * As SuperH uses the same address space for kernel and user data, we
 * can just do these as direct assignments.
 *
 * Careful to not
 * (a) re-use the arguments for side effects (sizeof is ok)
 * (b) require any knowledge of processes at this stage
 */
#define put_user(x,ptr)	__put_user_check((x),(ptr),sizeof(*(ptr)))
#define get_user(x,ptr) __get_user_check((x),(ptr),sizeof(*(ptr)))

/*
 * The "__xxx" versions do not do address space checking, useful when
 * doing multiple accesses to the same area (the user has to do the
 * checks by hand with "access_ok()")
 */
#define __put_user(x,ptr) \
  __put_user_nocheck((__typeof__(*(ptr)))(x),(ptr),sizeof(*(ptr)))
#define __get_user(x,ptr) \
  __get_user_nocheck((x),(ptr),sizeof(*(ptr)))

struct __large_struct { unsigned long buf[100]; };
#define __m(x) (*(struct __large_struct __user *)(x))

#define __get_user_size(x,ptr,size,retval)			\
do {								\
	retval = 0;						\
	__chk_user_ptr(ptr);					\
	switch (size) {						\
	case 1:							\
		__get_user_asm(x, ptr, retval, "b");		\
		break;						\
	case 2:							\
		__get_user_asm(x, ptr, retval, "w");		\
		break;						\
	case 4:							\
		__get_user_asm(x, ptr, retval, "l");		\
		break;						\
	default:						\
		__get_user_unknown();				\
		break;						\
	}							\
} while (0)

#define __get_user_nocheck(x,ptr,size)				\
({								\
	long __gu_err, __gu_val;				\
	__get_user_size(__gu_val, (ptr), (size), __gu_err);	\
	(x) = (__typeof__(*(ptr)))__gu_val;			\
	__gu_err;						\
})

#ifdef CONFIG_MMU
#define __get_user_check(x,ptr,size)				\
({								\
	long __gu_err, __gu_val;				\
	__chk_user_ptr(ptr);					\
	switch (size) {						\
	case 1:							\
		__get_user_1(__gu_val, (ptr), __gu_err);	\
		break;						\
	case 2:							\
		__get_user_2(__gu_val, (ptr), __gu_err);	\
		break;						\
	case 4:							\
		__get_user_4(__gu_val, (ptr), __gu_err);	\
		break;						\
	default:						\
		__get_user_unknown();				\
		break;						\
	}							\
								\
	(x) = (__typeof__(*(ptr)))__gu_val;			\
	__gu_err;						\
})

#define __get_user_1(x,addr,err) ({		\
__asm__("stc	r7_bank, %1\n\t"		\
	"mov.l	@(8,%1), %1\n\t"		\
	"and	%2, %1\n\t"			\
	"cmp/pz	%1\n\t"				\
	"bt/s	1f\n\t"				\
	" mov	#0, %0\n\t"			\
	"0:\n"					\
	"mov	#-14, %0\n\t"			\
	"bra	2f\n\t"				\
	" mov	#0, %1\n"			\
	"1:\n\t"				\
	"mov.b	@%2, %1\n\t"			\
	"extu.b	%1, %1\n"			\
	"2:\n"					\
	".section	__ex_table,\"a\"\n\t"	\
	".long	1b, 0b\n\t"			\
	".previous"				\
	: "=&r" (err), "=&r" (x)		\
	: "r" (addr)				\
	: "t");					\
})

#define __get_user_2(x,addr,err) ({		\
__asm__("stc	r7_bank, %1\n\t"		\
	"mov.l	@(8,%1), %1\n\t"		\
	"and	%2, %1\n\t"			\
	"cmp/pz	%1\n\t"				\
	"bt/s	1f\n\t"				\
	" mov	#0, %0\n\t"			\
	"0:\n"					\
	"mov	#-14, %0\n\t"			\
	"bra	2f\n\t"				\
	" mov	#0, %1\n"			\
	"1:\n\t"				\
	"mov.w	@%2, %1\n\t"			\
	"extu.w	%1, %1\n"			\
	"2:\n"					\
	".section	__ex_table,\"a\"\n\t"	\
	".long	1b, 0b\n\t"			\
	".previous"				\
	: "=&r" (err), "=&r" (x)		\
	: "r" (addr)				\
	: "t");					\
})

#define __get_user_4(x,addr,err) ({		\
__asm__("stc	r7_bank, %1\n\t"		\
	"mov.l	@(8,%1), %1\n\t"		\
	"and	%2, %1\n\t"			\
	"cmp/pz	%1\n\t"				\
	"bt/s	1f\n\t"				\
	" mov	#0, %0\n\t"			\
	"0:\n"					\
	"mov	#-14, %0\n\t"			\
	"bra	2f\n\t"				\
	" mov	#0, %1\n"			\
	"1:\n\t"				\
	"mov.l	@%2, %1\n\t"			\
	"2:\n"					\
	".section	__ex_table,\"a\"\n\t"	\
	".long	1b, 0b\n\t"			\
	".previous"				\
	: "=&r" (err), "=&r" (x)		\
	: "r" (addr)				\
	: "t");					\
})
#else /* CONFIG_MMU */
#define __get_user_check(x,ptr,size)					\
({									\
	long __gu_err, __gu_val;					\
	if (__access_ok((unsigned long)(ptr), (size))) {		\
		__get_user_size(__gu_val, (ptr), (size), __gu_err);	\
		(x) = (__typeof__(*(ptr)))__gu_val;			\
	} else								\
		__gu_err = -EFAULT;					\
	__gu_err;							\
})
#endif

#define __get_user_asm(x, addr, err, insn) \
({ \
__asm__ __volatile__( \
	"1:\n\t" \
	"mov." insn "	%2, %1\n\t" \
	"mov	#0, %0\n" \
	"2:\n" \
	".section	.fixup,\"ax\"\n" \
	"3:\n\t" \
	"mov	#0, %1\n\t" \
	"mov.l	4f, %0\n\t" \
	"jmp	@%0\n\t" \
	" mov	%3, %0\n" \
	"4:	.long	2b\n\t" \
	".previous\n" \
	".section	__ex_table,\"a\"\n\t" \
	".long	1b, 3b\n\t" \
	".previous" \
	:"=&r" (err), "=&r" (x) \
	:"m" (__m(addr)), "i" (-EFAULT)); })

extern void __get_user_unknown(void);

#define __put_user_size(x,ptr,size,retval)		\
do {							\
	retval = 0;					\
	__chk_user_ptr(ptr);				\
	switch (size) {					\
	case 1:						\
		__put_user_asm(x, ptr, retval, "b");	\
		break;					\
	case 2:						\
		__put_user_asm(x, ptr, retval, "w");	\
		break;					\
	case 4:						\
		__put_user_asm(x, ptr, retval, "l");	\
		break;					\
	case 8:						\
		__put_user_u64(x, ptr, retval);		\
		break;					\
	default:					\
		__put_user_unknown();			\
	}						\
} while (0)

#define __put_user_nocheck(x,ptr,size)			\
({							\
	long __pu_err;					\
	__put_user_size((x),(ptr),(size),__pu_err);	\
	__pu_err;					\
})

#define __put_user_check(x,ptr,size)				\
({								\
	long __pu_err = -EFAULT;				\
	__typeof__(*(ptr)) __user *__pu_addr = (ptr);		\
								\
	if (__access_ok((unsigned long)__pu_addr,size))		\
		__put_user_size((x),__pu_addr,(size),__pu_err);	\
	__pu_err;						\
})

#define __put_user_asm(x, addr, err, insn) \
({ \
__asm__ __volatile__( \
	"1:\n\t" \
	"mov." insn "	%1, %2\n\t" \
	"mov	#0, %0\n" \
	"2:\n" \
	".section	.fixup,\"ax\"\n" \
	"3:\n\t" \
	"nop\n\t" \
	"mov.l	4f, %0\n\t" \
	"jmp	@%0\n\t" \
	"mov	%3, %0\n" \
	"4:	.long	2b\n\t" \
	".previous\n" \
	".section	__ex_table,\"a\"\n\t" \
	".long	1b, 3b\n\t" \
	".previous" \
	:"=&r" (err) \
	:"r" (x), "m" (__m(addr)), "i" (-EFAULT) \
        :"memory"); })

#if defined(__LITTLE_ENDIAN__)
#define __put_user_u64(val,addr,retval) \
({ \
__asm__ __volatile__( \
	"1:\n\t" \
	"mov.l	%R1,%2\n\t" \
	"mov.l	%S1,%T2\n\t" \
	"mov	#0,%0\n" \
	"2:\n" \
	".section	.fixup,\"ax\"\n" \
	"3:\n\t" \
	"nop\n\t" \
	"mov.l	4f,%0\n\t" \
	"jmp	@%0\n\t" \
	" mov	%3,%0\n" \
	"4:	.long	2b\n\t" \
	".previous\n" \
	".section	__ex_table,\"a\"\n\t" \
	".long	1b, 3b\n\t" \
	".previous" \
	: "=r" (retval) \
	: "r" (val), "m" (__m(addr)), "i" (-EFAULT) \
        : "memory"); })
#else
#define __put_user_u64(val,addr,retval) \
({ \
__asm__ __volatile__( \
	"1:\n\t" \
	"mov.l	%S1,%2\n\t" \
	"mov.l	%R1,%T2\n\t" \
	"mov	#0,%0\n" \
	"2:\n" \
	".section	.fixup,\"ax\"\n" \
	"3:\n\t" \
	"nop\n\t" \
	"mov.l	4f,%0\n\t" \
	"jmp	@%0\n\t" \
	" mov	%3,%0\n" \
	"4:	.long	2b\n\t" \
	".previous\n" \
	".section	__ex_table,\"a\"\n\t" \
	".long	1b, 3b\n\t" \
	".previous" \
	: "=r" (retval) \
	: "r" (val), "m" (__m(addr)), "i" (-EFAULT) \
        : "memory"); })
#endif

extern void __put_user_unknown(void);

/* Generic arbitrary sized copy.  */
/* Return the number of bytes NOT copied */
__kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n);

#define copy_to_user(to,from,n) ({ \
void *__copy_to = (void *) (to); \
__kernel_size_t __copy_size = (__kernel_size_t) (n); \
__kernel_size_t __copy_res; \
if(__copy_size && __access_ok((unsigned long)__copy_to, __copy_size)) { \
__copy_res = __copy_user(__copy_to, (void *) (from), __copy_size); \
} else __copy_res = __copy_size; \
__copy_res; })

#define copy_from_user(to,from,n) ({ \
void *__copy_to = (void *) (to); \
void *__copy_from = (void *) (from); \
__kernel_size_t __copy_size = (__kernel_size_t) (n); \
__kernel_size_t __copy_res; \
if(__copy_size && __access_ok((unsigned long)__copy_from, __copy_size)) { \
__copy_res = __copy_user(__copy_to, __copy_from, __copy_size); \
} else __copy_res = __copy_size; \
__copy_res; })

static __always_inline unsigned long
__copy_from_user(void *to, const void __user *from, unsigned long n)
{
	return __copy_user(to, (__force void *)from, n);
}

static __always_inline unsigned long __must_check
__copy_to_user(void __user *to, const void *from, unsigned long n)
{
	return __copy_user((__force void *)to, from, n);
}

#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user

/*
 * Clear the area and return remaining number of bytes
 * (on failure.  Usually it's 0.)
 */
extern __kernel_size_t __clear_user(void *addr, __kernel_size_t size);

#define clear_user(addr,n) ({ \
void * __cl_addr = (addr); \
unsigned long __cl_size = (n); \
if (__cl_size && __access_ok(((unsigned long)(__cl_addr)), __cl_size)) \
__cl_size = __clear_user(__cl_addr, __cl_size); \
__cl_size; })

static __inline__ int
__strncpy_from_user(unsigned long __dest, unsigned long __user __src, int __count)
{
	__kernel_size_t res;
	unsigned long __dummy, _d, _s;

	__asm__ __volatile__(
		"9:\n"
		"mov.b	@%2+, %1\n\t"
		"cmp/eq	#0, %1\n\t"
		"bt/s	2f\n"
		"1:\n"
		"mov.b	%1, @%3\n\t"
		"dt	%7\n\t"
		"bf/s	9b\n\t"
		" add	#1, %3\n\t"
		"2:\n\t"
		"sub	%7, %0\n"
		"3:\n"
		".section .fixup,\"ax\"\n"
		"4:\n\t"
		"mov.l	5f, %1\n\t"
		"jmp	@%1\n\t"
		" mov	%8, %0\n\t"
		".balign 4\n"
		"5:	.long 3b\n"
		".previous\n"
		".section __ex_table,\"a\"\n"
		"	.balign 4\n"
		"	.long 9b,4b\n"
		".previous"
		: "=r" (res), "=&z" (__dummy), "=r" (_s), "=r" (_d)
		: "0" (__count), "2" (__src), "3" (__dest), "r" (__count),
		  "i" (-EFAULT)
		: "memory", "t");

	return res;
}

#define strncpy_from_user(dest,src,count) ({ \
unsigned long __sfu_src = (unsigned long) (src); \
int __sfu_count = (int) (count); \
long __sfu_res = -EFAULT; \
if(__access_ok(__sfu_src, __sfu_count)) { \
__sfu_res = __strncpy_from_user((unsigned long) (dest), __sfu_src, __sfu_count); \
} __sfu_res; })

/*
 * Return the size of a string (including the ending 0!)
 */
static __inline__ long __strnlen_user(const char __user *__s, long __n)
{
	unsigned long res;
	unsigned long __dummy;

	__asm__ __volatile__(
		"9:\n"
		"cmp/eq	%4, %0\n\t"
		"bt	2f\n"
		"1:\t"
		"mov.b	@(%0,%3), %1\n\t"
		"tst	%1, %1\n\t"
		"bf/s	9b\n\t"
		" add	#1, %0\n"
		"2:\n"
		".section .fixup,\"ax\"\n"
		"3:\n\t"
		"mov.l	4f, %1\n\t"
		"jmp	@%1\n\t"
		" mov	#0, %0\n"
		".balign 4\n"
		"4:	.long 2b\n"
		".previous\n"
		".section __ex_table,\"a\"\n"
		"	.balign 4\n"
		"	.long 1b,3b\n"
		".previous"
		: "=z" (res), "=&r" (__dummy)
		: "0" (0), "r" (__s), "r" (__n)
		: "t");
	return res;
}

static __inline__ long strnlen_user(const char __user *s, long n)
{
	if (!__addr_ok(s))
		return 0;
	else
		return __strnlen_user(s, n);
}

#define strlen_user(str)	strnlen_user(str, ~0UL >> 1)

/*
 * The exception table consists of pairs of addresses: the first is the
 * address of an instruction that is allowed to fault, and the second is
 * the address at which the program should continue.  No registers are
 * modified, so it is entirely up to the continuation code to figure out
 * what to do.
 *
 * All the routines below use bits of fixup code that are out of line
 * with the main instruction path.  This means when everything is well,
 * we don't even have to jump over them.  Further, they do not intrude
 * on our cache or tlb entries.
 */

struct exception_table_entry
{
	unsigned long insn, fixup;
};

extern int fixup_exception(struct pt_regs *regs);

#endif /* __ASM_SH_UACCESS_H */
OpenPOWER on IntegriCloud