1 #ifndef __H8300_UACCESS_H
2 #define __H8300_UACCESS_H
3
4 /*
5 * User space memory access functions
6 */
7 #include <linux/sched.h>
8 #include <linux/mm.h>
9 #include <linux/string.h>
10
11 #include <asm/segment.h>
12
13 #define VERIFY_READ 0
14 #define VERIFY_WRITE 1
15
16 /* We let the MMU do all checking */
17 #define access_ok(type, addr, size) __access_ok((unsigned long)addr,size)
__access_ok(unsigned long addr,unsigned long size)18 static inline int __access_ok(unsigned long addr, unsigned long size)
19 {
20 #define RANGE_CHECK_OK(addr, size, lower, upper) \
21 (((addr) >= (lower)) && (((addr) + (size)) < (upper)))
22
23 extern unsigned long _ramend;
24 return(RANGE_CHECK_OK(addr, size, 0L, (unsigned long)&_ramend));
25 }
26
27 /*
28 * The exception table consists of pairs of addresses: the first is the
29 * address of an instruction that is allowed to fault, and the second is
30 * the address at which the program should continue. No registers are
31 * modified, so it is entirely up to the continuation code to figure out
32 * what to do.
33 *
34 * All the routines below use bits of fixup code that are out of line
35 * with the main instruction path. This means when everything is well,
36 * we don't even have to jump over them. Further, they do not intrude
37 * on our cache or tlb entries.
38 */
39
40 struct exception_table_entry
41 {
42 unsigned long insn, fixup;
43 };
44
45 /* Returns 0 if exception not found and fixup otherwise. */
46 extern unsigned long search_exception_table(unsigned long);
47
48
49 /*
50 * These are the main single-value transfer routines. They automatically
51 * use the right size if we just have the right pointer type.
52 */
53
54 #define put_user(x, ptr) \
55 ({ \
56 int __pu_err = 0; \
57 typeof(*(ptr)) __pu_val = (x); \
58 switch (sizeof (*(ptr))) { \
59 case 1: \
60 case 2: \
61 case 4: \
62 *(ptr) = (__pu_val); \
63 break; \
64 case 8: \
65 memcpy(ptr, &__pu_val, sizeof (*(ptr))); \
66 break; \
67 default: \
68 __pu_err = __put_user_bad(); \
69 break; \
70 } \
71 __pu_err; \
72 })
73 #define __put_user(x, ptr) put_user(x, ptr)
74
75 extern int __put_user_bad(void);
76
77 /*
78 * Tell gcc we read from memory instead of writing: this is because
79 * we do not write to any memory gcc knows about, so there are no
80 * aliasing issues.
81 */
82
83 #define __ptr(x) ((unsigned long *)(x))
84
85 /*
86 * Tell gcc we read from memory instead of writing: this is because
87 * we do not write to any memory gcc knows about, so there are no
88 * aliasing issues.
89 */
90
91 #define get_user(x, ptr) \
92 ({ \
93 int __gu_err = 0; \
94 typeof(*(ptr)) __gu_val = *ptr; \
95 switch (sizeof(*(ptr))) { \
96 case 1: \
97 case 2: \
98 case 4: \
99 case 8: \
100 break; \
101 default: \
102 __gu_err = __get_user_bad(); \
103 __gu_val = 0; \
104 break; \
105 } \
106 (x) = __gu_val; \
107 __gu_err; \
108 })
109 #define __get_user(x, ptr) get_user(x, ptr)
110
111 extern int __get_user_bad(void);
112
113 #define copy_from_user(to, from, n) (memcpy(to, from, n), 0)
114 #define copy_to_user(to, from, n) (memcpy(to, from, n), 0)
115
116 #define __copy_from_user(to, from, n) copy_from_user(to, from, n)
117 #define __copy_to_user(to, from, n) copy_to_user(to, from, n)
118 #define __copy_to_user_inatomic __copy_to_user
119 #define __copy_from_user_inatomic __copy_from_user
120
121 #define copy_to_user_ret(to,from,n,retval) ({ if (copy_to_user(to,from,n)) return retval; })
122
123 #define copy_from_user_ret(to,from,n,retval) ({ if (copy_from_user(to,from,n)) return retval; })
124
125 /*
126 * Copy a null terminated string from userspace.
127 */
128
129 static inline long
strncpy_from_user(char * dst,const char * src,long count)130 strncpy_from_user(char *dst, const char *src, long count)
131 {
132 char *tmp;
133 strncpy(dst, src, count);
134 for (tmp = dst; *tmp && count > 0; tmp++, count--)
135 ;
136 return(tmp - dst); /* DAVIDM should we count a NUL ? check getname */
137 }
138
139 /*
140 * Return the size of a string (including the ending 0)
141 *
142 * Return 0 on exception, a value greater than N if too long
143 */
strnlen_user(const char * src,long n)144 static inline long strnlen_user(const char *src, long n)
145 {
146 return(strlen(src) + 1); /* DAVIDM make safer */
147 }
148
149 #define strlen_user(str) strnlen_user(str, 32767)
150
151 /*
152 * Zero Userspace
153 */
154
155 static inline unsigned long
clear_user(void * to,unsigned long n)156 clear_user(void *to, unsigned long n)
157 {
158 memset(to, 0, n);
159 return 0;
160 }
161
162 #endif /* _H8300_UACCESS_H */
163