aboutsummaryrefslogtreecommitdiffstats
path: root/arch/microblaze/include/asm/uaccess.h
blob: 5431b4631a7ad479bc23baf72de4563c68b8efb8 (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
/*
 * Copyright (C) 2008-2009 Michal Simek <monstr@monstr.eu>
 * Copyright (C) 2008-2009 PetaLogix
 * Copyright (C) 2006 Atmark Techno, Inc.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License. See the file "COPYING" in the main directory of this archive
 * for more details.
 */

#ifndef _ASM_MICROBLAZE_UACCESS_H
#define _ASM_MICROBLAZE_UACCESS_H

#ifdef __KERNEL__
#ifndef __ASSEMBLY__

#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/sched.h> /* RLIMIT_FSIZE */
#include <linux/mm.h>

#include <asm/mmu.h>
#include <asm/page.h>
#include <asm/pgtable.h>
#include <asm/segment.h>
#include <linux/string.h>

#define VERIFY_READ	0
#define VERIFY_WRITE	1

#define __clear_user(addr, n)	(memset((void *)(addr), 0, (n)), 0)

#ifndef CONFIG_MMU

extern int ___range_ok(unsigned long addr, unsigned long size);

#define __range_ok(addr, size) \
		___range_ok((unsigned long)(addr), (unsigned long)(size))

#define access_ok(type, addr, size) (__range_ok((addr), (size)) == 0)
#define __access_ok(add, size) (__range_ok((addr), (size)) == 0)

/* Undefined function to trigger linker error */
extern int bad_user_access_length(void);

/* FIXME this is function for optimalization -> memcpy */
#define __get_user(var, ptr)				\
({							\
	int __gu_err = 0;				\
	switch (sizeof(*(ptr))) {			\
	case 1:						\
	case 2:						\
	case 4:						\
		(var) = *(ptr);				\
		break;					\
	case 8:						\
		memcpy((void *) &(var), (ptr), 8);	\
		break;					\
	default:					\
		(var) = 0;				\
		__gu_err = __get_user_bad();		\
		break;					\
	}						\
	__gu_err;					\
})

#define __get_user_bad()	(bad_user_access_length(), (-EFAULT))

/* FIXME is not there defined __pu_val */
#define __put_user(var, ptr)					\
({								\
	int __pu_err = 0;					\
	switch (sizeof(*(ptr))) {				\
	case 1:							\
	case 2:							\
	case 4:							\
		*(ptr) = (var);					\
		break;						\
	case 8: {						\
		typeof(*(ptr)) __pu_val = (var);		\
		memcpy(ptr, &__pu_val, sizeof(__pu_val));	\
		}						\
		break;						\
	default:						\
		__pu_err = __put_user_bad();			\
		break;						\
	}							\
	__pu_err;						\
})

#define __put_user_bad()	(bad_user_access_length(), (-EFAULT))

#define put_user(x, ptr)	__put_user((x), (ptr))
#define get_user(x, ptr)	__get_user((x), (ptr))

#define copy_to_user(to, from, n)	(memcpy((to), (from), (n)), 0)
#define copy_from_user(to, from, n)	(memcpy((to), (from), (n)), 0)

#define __copy_to_user(to, from, n)	(copy_to_user((to), (from), (n)))
#define __copy_from_user(to, from, n)	(copy_from_user((to), (from), (n)))
#define __copy_to_user_inatomic(to, from, n) \
			(__copy_to_user((to), (from), (n)))
#define __copy_from_user_inatomic(to, from, n) \
			(__copy_from_user((to), (from), (n)))

static inline unsigned long clear_user(void *addr, unsigned long size)
{
	if (access_ok(VERIFY_WRITE, addr, size))
		size = __clear_user(addr, size);
	return size;
}

/* Returns 0 if exception not found and fixup otherwise.  */
extern unsigned long search_exception_table(unsigned long);

extern long strncpy_from_user(char *dst, const char *src, long count);
extern long strnlen_user(const char *src, long count);

#else /* CONFIG_MMU */

/*
 * Address is valid if:
 *  - "addr", "addr + size" and "size" are all below the limit
 */
#define access_ok(type, addr, size) \
	(get_fs().seg > (((unsigned long)(addr)) | \
		(size) | ((unsigned long)(addr) + (size))))

/* || printk("access_ok failed for %s at 0x%08lx (size %d), seg 0x%08x\n",
 type?"WRITE":"READ",addr,size,get_fs().seg)) */

/*
 * All the __XXX versions macros/functions below do not perform
 * access checking. It is assumed that the necessary checks have been
 * already performed before the finction (macro) is called.
 */

#define get_user(x, ptr)						\
({									\
	access_ok(VERIFY_READ, (ptr), sizeof(*(ptr)))			\
		? __get_user((x), (ptr)) : -EFAULT;			\
})

#define put_user(x, ptr)						\
({									\
	access_ok(VERIFY_WRITE, (ptr), sizeof(*(ptr)))			\
		? __put_user((x), (ptr)) : -EFAULT;			\
})

#define __get_user(x, ptr)						\
({									\
	unsigned long __gu_val;						\
	/*unsigned long __gu_ptr = (unsigned long)(ptr);*/		\
	long __gu_err;							\
	switch (sizeof(*(ptr))) {					\
	case 1:								\
		__get_user_asm("lbu", (ptr), __gu_val, __gu_err);	\
		break;							\
	case 2:								\
		__get_user_asm("lhu", (ptr), __gu_val, __gu_err);	\
		break;							\
	case 4:								\
		__get_user_asm("lw", (ptr), __gu_val, __gu_err);	\
		break;							\
	default:							\
		__gu_val = 0; __gu_err = -EINVAL;			\
	}								\
	x = (__typeof__(*(ptr))) __gu_val;				\
	__gu_err;							\
})

#define __get_user_asm(insn, __gu_ptr, __gu_val, __gu_err)		\
({									\
	__asm__ __volatile__ (						\
			"1:"	insn	" %1, %2, r0;			\
				addk	%0, r0, r0;			\
			2:						\
			.section .fixup,\"ax\";				\
			3:	brid	2b;				\
				addik	%0, r0, %3;			\
			.previous;					\
			.section __ex_table,\"a\";			\
			.word	1b,3b;					\
			.previous;"					\
		: "=r"(__gu_err), "=r"(__gu_val)			\
		: "r"(__gu_ptr), "i"(-EFAULT)				\
	);								\
})

#define __put_user(x, ptr)						\
({									\
	__typeof__(*(ptr)) volatile __gu_val = (x);			\
	long __gu_err = 0;						\
	switch (sizeof(__gu_val)) {					\
	case 1:								\
		__put_user_asm("sb", (ptr), __gu_val, __gu_err);	\
		break;							\
	case 2: 							\
		__put_user_asm("sh", (ptr), __gu_val, __gu_err);	\
		break;							\
	case 4:								\
		__put_user_asm("sw", (ptr), __gu_val, __gu_err);	\
		break;							\
	case 8:								\
		__put_user_asm_8((ptr), __gu_val, __gu_err);		\
		break;							\
	default:							\
		__gu_err = -EINVAL;					\
	}								\
	__gu_err;							\
})

#define __put_user_asm_8(__gu_ptr, __gu_val, __gu_err)	\
({							\
__asm__ __volatile__ ("	lwi	%0, %1, 0;		\
		1:	swi	%0, %2, 0;		\
			lwi	%0, %1, 4;		\
		2:	swi	%0, %2, 4;		\
			addk	%0,r0,r0;		\
		3:					\
		.section .fixup,\"ax\";			\
		4:	brid	3b;			\
			addik	%0, r0, %3;		\
		.previous;				\
		.section __ex_table,\"a\";		\
		.word	1b,4b,2b,4b;			\
		.previous;"				\
	: "=&r"(__gu_err)				\
	: "r"(&__gu_val),				\
	"r"(__gu_ptr), "i"(-EFAULT)			\
	);						\
})

#define __put_user_asm(insn, __gu_ptr, __gu_val, __gu_err)	\
({								\
	__asm__ __volatile__ (					\
			"1:"	insn	" %1, %2, r0;		\
				addk	%0, r0, r0;		\
			2:					\
			.section .fixup,\"ax\";			\
			3:	brid	2b;			\
				addik	%0, r0, %3;		\
			.previous;				\
			.section __ex_table,\"a\";		\
			.word	1b,3b;				\
			.previous;"				\
		: "=r"(__gu_err)				\
		: "r"(__gu_val), "r"(__gu_ptr), "i"(-EFAULT)	\
	);							\
})

/*
 * Return: number of not copied bytes, i.e. 0 if OK or non-zero if fail.
 */
static inline int clear_user(char *to, int size)
{
	if (size && access_ok(VERIFY_WRITE, to, size)) {
		__asm__ __volatile__ ("				\
				1:				\
					sb	r0, %2, r0;	\
					addik	%0, %0, -1;	\
					bneid	%0, 1b;		\
					addik	%2, %2, 1;	\
				2:				\
				.section __ex_table,\"a\";	\
				.word	1b,2b;			\
				.section .text;"		\
			: "=r"(size)				\
			: "0"(size), "r"(to)
		);
	}
	return size;
}

extern unsigned long __copy_tofrom_user(void __user *to,
		const void __user *from, unsigned long size);

#define copy_to_user(to, from, n)					\
	(access_ok(VERIFY_WRITE, (to), (n)) ?				\
		__copy_tofrom_user((void __user *)(to),			\
			(__force const void __user *)(from), (n))	\
		: -EFAULT)

#define __copy_to_user(to, from, n)	copy_to_user((to), (from), (n))
#define __copy_to_user_inatomic(to, from, n)	copy_to_user((to), (from), (n))

#define copy_from_user(to, from, n)					\
	(access_ok(VERIFY_READ, (from), (n)) ?				\
		__copy_tofrom_user((__force void __user *)(to),		\
			(void __user *)(from), (n))			\
		: -EFAULT)

#define __copy_from_user(to, from, n)	copy_from_user((to), (from), (n))
#define __copy_from_user_inatomic(to, from, n) \
		copy_from_user((to), (from), (n))

extern int __strncpy_user(char *to, const char __user *from, int len);
extern int __strnlen_user(const char __user *sstr, int len);

#define strncpy_from_user(to, from, len)	\
		(access_ok(VERIFY_READ, from, 1) ?	\
			__strncpy_user(to, from, len) : -EFAULT)
#define strnlen_user(str, len)	\
		(access_ok(VERIFY_READ, str, 1) ? __strnlen_user(str, len) : 0)

#endif /* CONFIG_MMU */

/*
 * 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;
};

#endif  /* __ASSEMBLY__ */
#endif /* __KERNEL__ */

#endif /* _ASM_MICROBLAZE_UACCESS_H */