summaryrefslogtreecommitdiff
path: root/arch/mn10300/include/asm/uaccess.h
blob: 5af468fd13596c4f98202d5b3b60d1e620daae7d (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
/* MN10300 userspace access functions
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells (dhowells@redhat.com)
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public Licence
 * as published by the Free Software Foundation; either version
 * 2 of the Licence, or (at your option) any later version.
 */
#ifndef _ASM_UACCESS_H
#define _ASM_UACCESS_H

/*
 * User space memory access functions
 */
#include <linux/kernel.h>
#include <asm/page.h>

/*
 * 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, these macros are grossly misnamed.
 */
#define MAKE_MM_SEG(s)	((mm_segment_t) { (s) })

#define KERNEL_XDS	MAKE_MM_SEG(0xBFFFFFFF)
#define KERNEL_DS	MAKE_MM_SEG(0x9FFFFFFF)
#define USER_DS		MAKE_MM_SEG(TASK_SIZE)

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

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

#define __addr_ok(addr) \
	((unsigned long)(addr) < (current_thread_info()->addr_limit.seg))

/*
 * check that a range of addresses falls within the current address limit
 */
static inline int ___range_ok(unsigned long addr, unsigned int size)
{
	int flag = 1, tmp;

	asm("	add	%3,%1	\n"	/* set C-flag if addr + size > 4Gb */
	    "	bcs	0f	\n"
	    "	cmp	%4,%1	\n"	/* jump if addr+size>limit (error) */
	    "	bhi	0f	\n"
	    "	clr	%0	\n"	/* mark okay */
	    "0:			\n"
	    : "=r"(flag), "=&r"(tmp)
	    : "1"(addr), "ir"(size),
	      "r"(current_thread_info()->addr_limit.seg), "0"(flag)
	    : "cc"
	    );

	return flag;
}

#define __range_ok(addr, size) ___range_ok((unsigned long)(addr), (u32)(size))

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

#include <asm/extable.h>

#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((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 *)(x))

#define __get_user_nocheck(x, ptr, size)				\
({									\
	unsigned long __gu_addr;					\
	int __gu_err;							\
	__gu_addr = (unsigned long) (ptr);				\
	switch (size) {							\
	case 1: {							\
		unsigned char __gu_val;					\
		__get_user_asm("bu");					\
		(x) = *(__force __typeof__(*(ptr))*) &__gu_val;		\
		break;							\
	}								\
	case 2: {							\
		unsigned short __gu_val;				\
		__get_user_asm("hu");					\
		(x) = *(__force __typeof__(*(ptr))*) &__gu_val;		\
		break;							\
	}								\
	case 4: {							\
		unsigned int __gu_val;					\
		__get_user_asm("");					\
		(x) = *(__force __typeof__(*(ptr))*) &__gu_val;		\
		break;							\
	}								\
	default:							\
		__get_user_unknown();					\
		break;							\
	}								\
	__gu_err;							\
})

#define __get_user_check(x, ptr, size)					\
({									\
	const __typeof__(*(ptr))* __guc_ptr = (ptr);			\
	int _e;								\
	if (likely(__access_ok((unsigned long) __guc_ptr, (size))))	\
		_e = __get_user_nocheck((x), __guc_ptr, (size));	\
	else {								\
		_e = -EFAULT;						\
		(x) = (__typeof__(x))0;					\
	}								\
	_e;								\
})

#define __get_user_asm(INSN)					\
({								\
	asm volatile(					\
		"1:\n"						\
		"	mov"INSN"	%2,%1\n"		\
		"	mov		0,%0\n"			\
		"2:\n"						\
		"	.section	.fixup,\"ax\"\n"	\
		"3:\n\t"					\
		"	mov		0,%1\n"			\
		"	mov		%3,%0\n"		\
		"	jmp		2b\n"			\
		"	.previous\n"				\
		"	.section	__ex_table,\"a\"\n"	\
		"	.balign		4\n"			\
		"	.long		1b, 3b\n"		\
		"	.previous"				\
		: "=&r" (__gu_err), "=&r" (__gu_val)		\
		: "m" (__m(__gu_addr)), "i" (-EFAULT));		\
})

extern int __get_user_unknown(void);

#define __put_user_nocheck(x, ptr, size)			\
({								\
	union {							\
		__typeof__(*(ptr)) val;				\
		u32 bits[2];					\
	} __pu_val;						\
	unsigned long __pu_addr;				\
	int __pu_err;						\
	__pu_val.val = (x);					\
	__pu_addr = (unsigned long) (ptr);			\
	switch (size) {						\
	case 1:  __put_user_asm("bu"); break;			\
	case 2:  __put_user_asm("hu"); break;			\
	case 4:  __put_user_asm(""  ); break;			\
	case 8:  __put_user_asm8();    break;			\
	default: __pu_err = __put_user_unknown(); break;	\
	}							\
	__pu_err;						\
})

#define __put_user_check(x, ptr, size)					\
({									\
	union {								\
		__typeof__(*(ptr)) val;					\
		u32 bits[2];						\
	} __pu_val;							\
	unsigned long __pu_addr;					\
	int __pu_err;							\
	__pu_val.val = (x);						\
	__pu_addr = (unsigned long) (ptr);				\
	if (likely(__access_ok(__pu_addr, size))) {			\
		switch (size) {						\
		case 1:  __put_user_asm("bu"); break;			\
		case 2:  __put_user_asm("hu"); break;			\
		case 4:  __put_user_asm(""  ); break;			\
		case 8:  __put_user_asm8();    break;			\
		default: __pu_err = __put_user_unknown(); break;	\
		}							\
	}								\
	else {								\
		__pu_err = -EFAULT;					\
	}								\
	__pu_err;							\
})

#define __put_user_asm(INSN)					\
({								\
	asm volatile(						\
		"1:\n"						\
		"	mov"INSN"	%1,%2\n"		\
		"	mov		0,%0\n"			\
		"2:\n"						\
		"	.section	.fixup,\"ax\"\n"	\
		"3:\n"						\
		"	mov		%3,%0\n"		\
		"	jmp		2b\n"			\
		"	.previous\n"				\
		"	.section	__ex_table,\"a\"\n"	\
		"	.balign		4\n"			\
		"	.long		1b, 3b\n"		\
		"	.previous"				\
		: "=&r" (__pu_err)				\
		: "r" (__pu_val.val), "m" (__m(__pu_addr)),	\
		  "i" (-EFAULT)					\
		);						\
})

#define __put_user_asm8()						\
({									\
	asm volatile(							\
		"1:	mov		%1,%3		\n"		\
		"2:	mov		%2,%4		\n"		\
		"	mov		0,%0		\n"		\
		"3:					\n"		\
		"	.section	.fixup,\"ax\"	\n"		\
		"4:					\n"		\
		"	mov		%5,%0		\n"		\
		"	jmp		3b		\n"		\
		"	.previous			\n"		\
		"	.section	__ex_table,\"a\"\n"		\
		"	.balign		4		\n"		\
		"	.long		1b, 4b		\n"		\
		"	.long		2b, 4b		\n"		\
		"	.previous			\n"		\
		: "=&r" (__pu_err)					\
		: "r" (__pu_val.bits[0]), "r" (__pu_val.bits[1]),	\
		  "m" (__m(__pu_addr)), "m" (__m(__pu_addr+4)),		\
		  "i" (-EFAULT)						\
		);							\
})

extern int __put_user_unknown(void);


/*
 * Copy To/From Userspace
 */
/* Generic arbitrary sized copy.  */
#define __copy_user(to, from, size)					\
do {									\
	if (size) {							\
		void *__to = to;					\
		const void *__from = from;				\
		int w;							\
		asm volatile(						\
			"0:     movbu	(%0),%3;\n"			\
			"1:     movbu	%3,(%1);\n"			\
			"	inc	%0;\n"				\
			"	inc	%1;\n"				\
			"       add	-1,%2;\n"			\
			"       bne	0b;\n"				\
			"2:\n"						\
			"	.section .fixup,\"ax\"\n"		\
			"3:	jmp	2b\n"				\
			"	.previous\n"				\
			"	.section __ex_table,\"a\"\n"		\
			"       .balign	4\n"				\
			"       .long	0b,3b\n"			\
			"       .long	1b,3b\n"			\
			"	.previous\n"				\
			: "=a"(__from), "=a"(__to), "=r"(size), "=&r"(w)\
			: "0"(__from), "1"(__to), "2"(size)		\
			: "cc", "memory");				\
	}								\
} while (0)

static inline unsigned long
raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
	__copy_user(to, from, n);
	return n;
}

static inline unsigned long
raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
	__copy_user(to, from, n);
	return n;
}

extern long strncpy_from_user(char *dst, const char __user *src, long count);
extern long strnlen_user(const char __user *str, long n);
extern unsigned long clear_user(void __user *mem, unsigned long len);
extern unsigned long __clear_user(void __user *mem, unsigned long len);

#endif /* _ASM_UACCESS_H */