summaryrefslogtreecommitdiffstats
path: root/arch/m68k/include/asm/uaccess_mm.h
blob: 9c80cd515b2069cab1a28b2b54a16f70d9a19028 (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
#ifndef __M68K_UACCESS_H
#define __M68K_UACCESS_H

/*
 * User space memory access functions
 */
#include <linux/compiler.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/sched.h>
#include <asm/segment.h>

#define VERIFY_READ	0
#define VERIFY_WRITE	1

/* We let the MMU do all checking */
static inline int access_ok(int type, const void __user *addr,
			    unsigned long size)
{
	return 1;
}

/*
 * Not all varients of the 68k family support the notion of address spaces.
 * The traditional 680x0 parts do, and they use the sfc/dfc registers and
 * the "moves" instruction to access user space from kernel space. Other
 * family members like ColdFire don't support this, and only have a single
 * address space, and use the usual "move" instruction for user space access.
 *
 * Outside of this difference the user space access functions are the same.
 * So lets keep the code simple and just define in what we need to use.
 */
#ifdef CONFIG_CPU_HAS_ADDRESS_SPACES
#define	MOVES	"moves"
#else
#define	MOVES	"move"
#endif

/*
 * 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 __put_user_bad(void);
extern int __get_user_bad(void);

#define __put_user_asm(res, x, ptr, bwl, reg, err)	\
asm volatile ("\n"					\
	"1:	"MOVES"."#bwl"	%2,%1\n"		\
	"2:\n"						\
	"	.section .fixup,\"ax\"\n"		\
	"	.even\n"				\
	"10:	moveq.l	%3,%0\n"			\
	"	jra 2b\n"				\
	"	.previous\n"				\
	"\n"						\
	"	.section __ex_table,\"a\"\n"		\
	"	.align	4\n"				\
	"	.long	1b,10b\n"			\
	"	.long	2b,10b\n"			\
	"	.previous"				\
	: "+d" (res), "=m" (*(ptr))			\
	: #reg (x), "i" (err))

/*
 * 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)) __pu_val = (x);					\
	int __pu_err = 0;						\
	__chk_user_ptr(ptr);						\
	switch (sizeof (*(ptr))) {					\
	case 1:								\
		__put_user_asm(__pu_err, __pu_val, ptr, b, d, -EFAULT);	\
		break;							\
	case 2:								\
		__put_user_asm(__pu_err, __pu_val, ptr, w, d, -EFAULT);	\
		break;							\
	case 4:								\
		__put_user_asm(__pu_err, __pu_val, ptr, l, r, -EFAULT);	\
		break;							\
	case 8:								\
 	    {								\
 		const void __user *__pu_ptr = (ptr);			\
		asm volatile ("\n"					\
			"1:	"MOVES".l	%2,(%1)+\n"		\
			"2:	"MOVES".l	%R2,(%1)\n"		\
			"3:\n"						\
			"	.section .fixup,\"ax\"\n"		\
			"	.even\n"				\
			"10:	movel %3,%0\n"				\
			"	jra 3b\n"				\
			"	.previous\n"				\
			"\n"						\
			"	.section __ex_table,\"a\"\n"		\
			"	.align 4\n"				\
			"	.long 1b,10b\n"				\
			"	.long 2b,10b\n"				\
			"	.long 3b,10b\n"				\
			"	.previous"				\
			: "+d" (__pu_err), "+a" (__pu_ptr)		\
			: "r" (__pu_val), "i" (-EFAULT)			\
			: "memory");					\
		break;							\
	    }								\
	default:							\
		__pu_err = __put_user_bad();				\
		break;							\
	}								\
	__pu_err;							\
})
#define put_user(x, ptr)	__put_user(x, ptr)


#define __get_user_asm(res, x, ptr, type, bwl, reg, err) ({	\
	type __gu_val;						\
	asm volatile ("\n"					\
		"1:	"MOVES"."#bwl"	%2,%1\n"		\
		"2:\n"						\
		"	.section .fixup,\"ax\"\n"		\
		"	.even\n"				\
		"10:	move.l	%3,%0\n"			\
		"	sub.l	%1,%1\n"			\
		"	jra	2b\n"				\
		"	.previous\n"				\
		"\n"						\
		"	.section __ex_table,\"a\"\n"		\
		"	.align	4\n"				\
		"	.long	1b,10b\n"			\
		"	.previous"				\
		: "+d" (res), "=&" #reg (__gu_val)		\
		: "m" (*(ptr)), "i" (err));			\
	(x) = (typeof(*(ptr)))(unsigned long)__gu_val;		\
})

#define __get_user(x, ptr)						\
({									\
	int __gu_err = 0;						\
	__chk_user_ptr(ptr);						\
	switch (sizeof(*(ptr))) {					\
	case 1:								\
		__get_user_asm(__gu_err, x, ptr, u8, b, d, -EFAULT);	\
		break;							\
	case 2:								\
		__get_user_asm(__gu_err, x, ptr, u16, w, d, -EFAULT);	\
		break;							\
	case 4:								\
		__get_user_asm(__gu_err, x, ptr, u32, l, r, -EFAULT);	\
		break;							\
/*	case 8:	disabled because gcc-4.1 has a broken typeof		\
 	    {								\
 		const void *__gu_ptr = (ptr);				\
 		u64 __gu_val;						\
		asm volatile ("\n"					\
			"1:	"MOVES".l	(%2)+,%1\n"		\
			"2:	"MOVES".l	(%2),%R1\n"		\
			"3:\n"						\
			"	.section .fixup,\"ax\"\n"		\
			"	.even\n"				\
			"10:	move.l	%3,%0\n"			\
			"	sub.l	%1,%1\n"			\
			"	sub.l	%R1,%R1\n"			\
			"	jra	3b\n"				\
			"	.previous\n"				\
			"\n"						\
			"	.section __ex_table,\"a\"\n"		\
			"	.align	4\n"				\
			"	.long	1b,10b\n"			\
			"	.long	2b,10b\n"			\
			"	.previous"				\
			: "+d" (__gu_err), "=&r" (__gu_val),		\
			  "+a" (__gu_ptr)				\
			: "i" (-EFAULT)					\
			: "memory");					\
		(x) = (typeof(*(ptr)))__gu_val;				\
		break;							\
	    }	*/							\
	default:							\
		__gu_err = __get_user_bad();				\
		break;							\
	}								\
	__gu_err;							\
})
#define get_user(x, ptr) __get_user(x, ptr)

unsigned long __generic_copy_from_user(void *to, const void __user *from, unsigned long n);
unsigned long __generic_copy_to_user(void __user *to, const void *from, unsigned long n);

#define __constant_copy_from_user_asm(res, to, from, tmp, n, s1, s2, s3)\
	asm volatile ("\n"						\
		"1:	"MOVES"."#s1"	(%2)+,%3\n"			\
		"	move."#s1"	%3,(%1)+\n"			\
		"2:	"MOVES"."#s2"	(%2)+,%3\n"			\
		"	move."#s2"	%3,(%1)+\n"			\
		"	.ifnc	\""#s3"\",\"\"\n"			\
		"3:	"MOVES"."#s3"	(%2)+,%3\n"			\
		"	move."#s3"	%3,(%1)+\n"			\
		"	.endif\n"					\
		"4:\n"							\
		"	.section __ex_table,\"a\"\n"			\
		"	.align	4\n"					\
		"	.long	1b,10f\n"				\
		"	.long	2b,20f\n"				\
		"	.ifnc	\""#s3"\",\"\"\n"			\
		"	.long	3b,30f\n"				\
		"	.endif\n"					\
		"	.previous\n"					\
		"\n"							\
		"	.section .fixup,\"ax\"\n"			\
		"	.even\n"					\
		"10:	clr."#s1"	(%1)+\n"			\
		"20:	clr."#s2"	(%1)+\n"			\
		"	.ifnc	\""#s3"\",\"\"\n"			\
		"30:	clr."#s3"	(%1)+\n"			\
		"	.endif\n"					\
		"	moveq.l	#"#n",%0\n"				\
		"	jra	4b\n"					\
		"	.previous\n"					\
		: "+d" (res), "+&a" (to), "+a" (from), "=&d" (tmp)	\
		: : "memory")

static __always_inline unsigned long
__constant_copy_from_user(void *to, const void __user *from, unsigned long n)
{
	unsigned long res = 0, tmp;

	switch (n) {
	case 1:
		__get_user_asm(res, *(u8 *)to, (u8 __user *)from, u8, b, d, 1);
		break;
	case 2:
		__get_user_asm(res, *(u16 *)to, (u16 __user *)from, u16, w, d, 2);
		break;
	case 3:
		__constant_copy_from_user_asm(res, to, from, tmp, 3, w, b,);
		break;
	case 4:
		__get_user_asm(res, *(u32 *)to, (u32 __user *)from, u32, l, r, 4);
		break;
	case 5:
		__constant_copy_from_user_asm(res, to, from, tmp, 5, l, b,);
		break;
	case 6:
		__constant_copy_from_user_asm(res, to, from, tmp, 6, l, w,);
		break;
	case 7:
		__constant_copy_from_user_asm(res, to, from, tmp, 7, l, w, b);
		break;
	case 8:
		__constant_copy_from_user_asm(res, to, from, tmp, 8, l, l,);
		break;
	case 9:
		__constant_copy_from_user_asm(res, to, from, tmp, 9, l, l, b);
		break;
	case 10:
		__constant_copy_from_user_asm(res, to, from, tmp, 10, l, l, w);
		break;
	case 12:
		__constant_copy_from_user_asm(res, to, from, tmp, 12, l, l, l);
		break;
	default:
		/* we limit the inlined version to 3 moves */
		return __generic_copy_from_user(to, from, n);
	}

	return res;
}

#define __constant_copy_to_user_asm(res, to, from, tmp, n, s1, s2, s3)	\
	asm volatile ("\n"						\
		"	move."#s1"	(%2)+,%3\n"			\
		"11:	"MOVES"."#s1"	%3,(%1)+\n"			\
		"12:	move."#s2"	(%2)+,%3\n"			\
		"21:	"MOVES"."#s2"	%3,(%1)+\n"			\
		"22:\n"							\
		"	.ifnc	\""#s3"\",\"\"\n"			\
		"	move."#s3"	(%2)+,%3\n"			\
		"31:	"MOVES"."#s3"	%3,(%1)+\n"			\
		"32:\n"							\
		"	.endif\n"					\
		"4:\n"							\
		"\n"							\
		"	.section __ex_table,\"a\"\n"			\
		"	.align	4\n"					\
		"	.long	11b,5f\n"				\
		"	.long	12b,5f\n"				\
		"	.long	21b,5f\n"				\
		"	.long	22b,5f\n"				\
		"	.ifnc	\""#s3"\",\"\"\n"			\
		"	.long	31b,5f\n"				\
		"	.long	32b,5f\n"				\
		"	.endif\n"					\
		"	.previous\n"					\
		"\n"							\
		"	.section .fixup,\"ax\"\n"			\
		"	.even\n"					\
		"5:	moveq.l	#"#n",%0\n"				\
		"	jra	4b\n"					\
		"	.previous\n"					\
		: "+d" (res), "+a" (to), "+a" (from), "=&d" (tmp)	\
		: : "memory")

static __always_inline unsigned long
__constant_copy_to_user(void __user *to, const void *from, unsigned long n)
{
	unsigned long res = 0, tmp;

	switch (n) {
	case 1:
		__put_user_asm(res, *(u8 *)from, (u8 __user *)to, b, d, 1);
		break;
	case 2:
		__put_user_asm(res, *(u16 *)from, (u16 __user *)to, w, d, 2);
		break;
	case 3:
		__constant_copy_to_user_asm(res, to, from, tmp, 3, w, b,);
		break;
	case 4:
		__put_user_asm(res, *(u32 *)from, (u32 __user *)to, l, r, 4);
		break;
	case 5:
		__constant_copy_to_user_asm(res, to, from, tmp, 5, l, b,);
		break;
	case 6:
		__constant_copy_to_user_asm(res, to, from, tmp, 6, l, w,);
		break;
	case 7:
		__constant_copy_to_user_asm(res, to, from, tmp, 7, l, w, b);
		break;
	case 8:
		__constant_copy_to_user_asm(res, to, from, tmp, 8, l, l,);
		break;
	case 9:
		__constant_copy_to_user_asm(res, to, from, tmp, 9, l, l, b);
		break;
	case 10:
		__constant_copy_to_user_asm(res, to, from, tmp, 10, l, l, w);
		break;
	case 12:
		__constant_copy_to_user_asm(res, to, from, tmp, 12, l, l, l);
		break;
	default:
		/* limit the inlined version to 3 moves */
		return __generic_copy_to_user(to, from, n);
	}

	return res;
}

#define __copy_from_user(to, from, n)		\
(__builtin_constant_p(n) ?			\
 __constant_copy_from_user(to, from, n) :	\
 __generic_copy_from_user(to, from, n))

#define __copy_to_user(to, from, n)		\
(__builtin_constant_p(n) ?			\
 __constant_copy_to_user(to, from, n) :		\
 __generic_copy_to_user(to, from, n))

#define __copy_to_user_inatomic		__copy_to_user
#define __copy_from_user_inatomic	__copy_from_user

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

long strncpy_from_user(char *dst, const char __user *src, long count);
long strnlen_user(const char __user *src, long n);
unsigned long __clear_user(void __user *to, unsigned long n);

#define clear_user	__clear_user

#define strlen_user(str) strnlen_user(str, 32767)

#endif /* _M68K_UACCESS_H */