1 /*
2  * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
3  * Licensed under the GPL
4  */
5 
6 #ifndef __UM_UACCESS_H
7 #define __UM_UACCESS_H
8 
9 #include <asm/errno.h>
10 #include <asm/processor.h>
11 
12 /* thread_info has a mm_segment_t in it, so put the definition up here */
13 typedef struct {
14 	unsigned long seg;
15 } mm_segment_t;
16 
17 #include "linux/thread_info.h"
18 
19 #define VERIFY_READ 0
20 #define VERIFY_WRITE 1
21 
22 /*
23  * The fs value determines whether argument validity checking should be
24  * performed or not.  If get_fs() == USER_DS, checking is performed, with
25  * get_fs() == KERNEL_DS, checking is bypassed.
26  *
27  * For historical reasons, these macros are grossly misnamed.
28  */
29 
30 #define MAKE_MM_SEG(s)	((mm_segment_t) { (s) })
31 
32 #define KERNEL_DS	MAKE_MM_SEG(0xFFFFFFFF)
33 #define USER_DS		MAKE_MM_SEG(TASK_SIZE)
34 
35 #define get_ds()	(KERNEL_DS)
36 #define get_fs()	(current_thread_info()->addr_limit)
37 #define set_fs(x)	(current_thread_info()->addr_limit = (x))
38 
39 #define segment_eq(a, b) ((a).seg == (b).seg)
40 
41 #include "um_uaccess.h"
42 
43 #define __copy_from_user(to, from, n) copy_from_user(to, from, n)
44 
45 #define __copy_to_user(to, from, n) copy_to_user(to, from, n)
46 
47 #define __copy_to_user_inatomic __copy_to_user
48 #define __copy_from_user_inatomic __copy_from_user
49 
50 #define __get_user(x, ptr) \
51 ({ \
52 	const __typeof__(*(ptr)) __user *__private_ptr = (ptr);	\
53 	__typeof__(x) __private_val;			\
54 	int __private_ret = -EFAULT;			\
55 	(x) = (__typeof__(*(__private_ptr)))0;				\
56 	if (__copy_from_user((__force void *)&__private_val, (__private_ptr),\
57 			     sizeof(*(__private_ptr))) == 0) {		\
58 		(x) = (__typeof__(*(__private_ptr))) __private_val;	\
59 		__private_ret = 0;					\
60 	}								\
61 	__private_ret;							\
62 })
63 
64 #define get_user(x, ptr) \
65 ({ \
66         const __typeof__((*(ptr))) __user *private_ptr = (ptr); \
67         (access_ok(VERIFY_READ, private_ptr, sizeof(*private_ptr)) ? \
68 	 __get_user(x, private_ptr) : ((x) = (__typeof__(*ptr))0, -EFAULT)); \
69 })
70 
71 #define __put_user(x, ptr) \
72 ({ \
73         __typeof__(*(ptr)) __user *__private_ptr = ptr; \
74         __typeof__(*(__private_ptr)) __private_val; \
75         int __private_ret = -EFAULT; \
76         __private_val = (__typeof__(*(__private_ptr))) (x); \
77         if (__copy_to_user((__private_ptr), &__private_val, \
78 			   sizeof(*(__private_ptr))) == 0) { \
79 		__private_ret = 0; \
80 	} \
81         __private_ret; \
82 })
83 
84 #define put_user(x, ptr) \
85 ({ \
86         __typeof__(*(ptr)) __user *private_ptr = (ptr); \
87         (access_ok(VERIFY_WRITE, private_ptr, sizeof(*private_ptr)) ? \
88 	 __put_user(x, private_ptr) : -EFAULT); \
89 })
90 
91 #define strlen_user(str) strnlen_user(str, ~0U >> 1)
92 
93 struct exception_table_entry
94 {
95         unsigned long insn;
96 	unsigned long fixup;
97 };
98 
99 #endif
100