summaryrefslogtreecommitdiff
path: root/arch/s390/include/asm/uaccess.h
blob: 304cfe44df50cc4df75b90e40c3ab52c1d011ac4 (plain) (blame)
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
/*
 *  S390 version
 *    Copyright IBM Corp. 1999, 2000
 *    Author(s): Hartmut Penner (hp@de.ibm.com),
 *               Martin Schwidefsky (schwidefsky@de.ibm.com)
 *
 *  Derived from "include/asm-i386/uaccess.h"
 */
#ifndef __S390_UACCESS_H
#define __S390_UACCESS_H

/*
 * User space memory access functions
 */
#include <asm/processor.h>
#include <asm/ctl_reg.h>
#include <asm/extable.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(a)  ((mm_segment_t) { (a) })


#define KERNEL_DS       MAKE_MM_SEG(0)
#define USER_DS         MAKE_MM_SEG(1)

#define get_ds()        (KERNEL_DS)
#define get_fs()        (current->thread.mm_segment)
#define segment_eq(a,b) ((a).ar4 == (b).ar4)

static inline void set_fs(mm_segment_t fs)
{
	current->thread.mm_segment = fs;
	if (uaccess_kernel()) {
		set_cpu_flag(CIF_ASCE_SECONDARY);
		__ctl_load(S390_lowcore.kernel_asce, 7, 7);
	} else {
		clear_cpu_flag(CIF_ASCE_SECONDARY);
		__ctl_load(S390_lowcore.user_asce, 7, 7);
	}
}

static inline int __range_ok(unsigned long addr, unsigned long size)
{
	return 1;
}

#define __access_ok(addr, size)				\
({							\
	__chk_user_ptr(addr);				\
	__range_ok((unsigned long)(addr), (size));	\
})

#define access_ok(type, addr, size) __access_ok(addr, size)

unsigned long __must_check
raw_copy_from_user(void *to, const void __user *from, unsigned long n);

unsigned long __must_check
raw_copy_to_user(void __user *to, const void *from, unsigned long n);

#define INLINE_COPY_FROM_USER
#define INLINE_COPY_TO_USER

#ifdef CONFIG_HAVE_MARCH_Z10_FEATURES

#define __put_get_user_asm(to, from, size, spec)		\
({								\
	register unsigned long __reg0 asm("0") = spec;		\
	int __rc;						\
								\
	asm volatile(						\
		"0:	mvcos	%1,%3,%2\n"			\
		"1:	xr	%0,%0\n"			\
		"2:\n"						\
		".pushsection .fixup, \"ax\"\n"			\
		"3:	lhi	%0,%5\n"			\
		"	jg	2b\n"				\
		".popsection\n"					\
		EX_TABLE(0b,3b) EX_TABLE(1b,3b)			\
		: "=d" (__rc), "+Q" (*(to))			\
		: "d" (size), "Q" (*(from)),			\
		  "d" (__reg0), "K" (-EFAULT)			\
		: "cc");					\
	__rc;							\
})

static inline int __put_user_fn(void *x, void __user *ptr, unsigned long size)
{
	unsigned long spec = 0x810000UL;
	int rc;

	switch (size) {
	case 1:
		rc = __put_get_user_asm((unsigned char __user *)ptr,
					(unsigned char *)x,
					size, spec);
		break;
	case 2:
		rc = __put_get_user_asm((unsigned short __user *)ptr,
					(unsigned short *)x,
					size, spec);
		break;
	case 4:
		rc = __put_get_user_asm((unsigned int __user *)ptr,
					(unsigned int *)x,
					size, spec);
		break;
	case 8:
		rc = __put_get_user_asm((unsigned long __user *)ptr,
					(unsigned long *)x,
					size, spec);
		break;
	}
	return rc;
}

static inline int __get_user_fn(void *x, const void __user *ptr, unsigned long size)
{
	unsigned long spec = 0x81UL;
	int rc;

	switch (size) {
	case 1:
		rc = __put_get_user_asm((unsigned char *)x,
					(unsigned char __user *)ptr,
					size, spec);
		break;
	case 2:
		rc = __put_get_user_asm((unsigned short *)x,
					(unsigned short __user *)ptr,
					size, spec);
		break;
	case 4:
		rc = __put_get_user_asm((unsigned int *)x,
					(unsigned int __user *)ptr,
					size, spec);
		break;
	case 8:
		rc = __put_get_user_asm((unsigned long *)x,
					(unsigned long __user *)ptr,
					size, spec);
		break;
	}
	return rc;
}

#else /* CONFIG_HAVE_MARCH_Z10_FEATURES */

static inline int __put_user_fn(void *x, void __user *ptr, unsigned long size)
{
	size = raw_copy_to_user(ptr, x, size);
	return size ? -EFAULT : 0;
}

static inline int __get_user_fn(void *x, const void __user *ptr, unsigned long size)
{
	size = raw_copy_from_user(x, ptr, size);
	return size ? -EFAULT : 0;
}

#endif /* CONFIG_HAVE_MARCH_Z10_FEATURES */

/*
 * These are the main single-value transfer routines.  They automatically
 * use the right size if we just have the right pointer type.
 */
#define __put_user(x, ptr) \
({								\
	__typeof__(*(ptr)) __x = (x);				\
	int __pu_err = -EFAULT;					\
        __chk_user_ptr(ptr);                                    \
	switch (sizeof (*(ptr))) {				\
	case 1:							\
	case 2:							\
	case 4:							\
	case 8:							\
		__pu_err = __put_user_fn(&__x, ptr,		\
					 sizeof(*(ptr)));	\
		break;						\
	default:						\
		__put_user_bad();				\
		break;						\
	 }							\
	__builtin_expect(__pu_err, 0);				\
})

#define put_user(x, ptr)					\
({								\
	might_fault();						\
	__put_user(x, ptr);					\
})


int __put_user_bad(void) __attribute__((noreturn));

#define __get_user(x, ptr)					\
({								\
	int __gu_err = -EFAULT;					\
	__chk_user_ptr(ptr);					\
	switch (sizeof(*(ptr))) {				\
	case 1: {						\
		unsigned char __x = 0;				\
		__gu_err = __get_user_fn(&__x, ptr,		\
					 sizeof(*(ptr)));	\
		(x) = *(__force __typeof__(*(ptr)) *) &__x;	\
		break;						\
	};							\
	case 2: {						\
		unsigned short __x = 0;				\
		__gu_err = __get_user_fn(&__x, ptr,		\
					 sizeof(*(ptr)));	\
		(x) = *(__force __typeof__(*(ptr)) *) &__x;	\
		break;						\
	};							\
	case 4: {						\
		unsigned int __x = 0;				\
		__gu_err = __get_user_fn(&__x, ptr,		\
					 sizeof(*(ptr)));	\
		(x) = *(__force __typeof__(*(ptr)) *) &__x;	\
		break;						\
	};							\
	case 8: {						\
		unsigned long long __x = 0;			\
		__gu_err = __get_user_fn(&__x, ptr,		\
					 sizeof(*(ptr)));	\
		(x) = *(__force __typeof__(*(ptr)) *) &__x;	\
		break;						\
	};							\
	default:						\
		__get_user_bad();				\
		break;						\
	}							\
	__builtin_expect(__gu_err, 0);				\
})

#define get_user(x, ptr)					\
({								\
	might_fault();						\
	__get_user(x, ptr);					\
})

int __get_user_bad(void) __attribute__((noreturn));

unsigned long __must_check
raw_copy_in_user(void __user *to, const void __user *from, unsigned long n);

/*
 * Copy a null terminated string from userspace.
 */

long __strncpy_from_user(char *dst, const char __user *src, long count);

static inline long __must_check
strncpy_from_user(char *dst, const char __user *src, long count)
{
	might_fault();
	return __strncpy_from_user(dst, src, count);
}

unsigned long __must_check __strnlen_user(const char __user *src, unsigned long count);

static inline unsigned long strnlen_user(const char __user *src, unsigned long n)
{
	might_fault();
	return __strnlen_user(src, n);
}

/*
 * Zero Userspace
 */
unsigned long __must_check __clear_user(void __user *to, unsigned long size);

static inline unsigned long __must_check clear_user(void __user *to, unsigned long n)
{
	might_fault();
	return __clear_user(to, n);
}

int copy_to_user_real(void __user *dest, void *src, unsigned long count);
void s390_kernel_write(void *dst, const void *src, size_t size);

#endif /* __S390_UACCESS_H */