1 #ifndef __M68KNOMMU_UACCESS_H
2 #define __M68KNOMMU_UACCESS_H
5 * User space memory access functions
7 #include <linux/sched.h>
9 #include <linux/string.h>
11 #include <asm/segment.h>
14 #define VERIFY_WRITE 1
16 #define access_ok(type,addr,size) _access_ok((unsigned long)(addr),(size))
19 * It is not enough to just have access_ok check for a real RAM address.
20 * This would disallow the case of code/ro-data running XIP in flash/rom.
21 * Ideally we would check the possible flash ranges too, but that is
22 * currently not so easy.
24 static inline int _access_ok(unsigned long addr, unsigned long size)
30 * The exception table consists of pairs of addresses: the first is the
31 * address of an instruction that is allowed to fault, and the second is
32 * the address at which the program should continue. No registers are
33 * modified, so it is entirely up to the continuation code to figure out
36 * All the routines below use bits of fixup code that are out of line
37 * with the main instruction path. This means when everything is well,
38 * we don't even have to jump over them. Further, they do not intrude
39 * on our cache or tlb entries.
42 struct exception_table_entry
44 unsigned long insn, fixup;
49 * These are the main single-value transfer routines. They automatically
50 * use the right size if we just have the right pointer type.
53 #define put_user(x, ptr) \
56 typeof(*(ptr)) __pu_val = (x); \
57 switch (sizeof (*(ptr))) { \
59 __put_user_asm(__pu_err, __pu_val, ptr, b); \
62 __put_user_asm(__pu_err, __pu_val, ptr, w); \
65 __put_user_asm(__pu_err, __pu_val, ptr, l); \
68 memcpy(ptr, &__pu_val, sizeof (*(ptr))); \
71 __pu_err = __put_user_bad(); \
76 #define __put_user(x, ptr) put_user(x, ptr)
78 extern int __put_user_bad(void);
81 * Tell gcc we read from memory instead of writing: this is because
82 * we do not write to any memory gcc knows about, so there are no
86 #define __ptr(x) ((unsigned long *)(x))
88 #define __put_user_asm(err,x,ptr,bwl) \
89 __asm__ ("move" #bwl " %0,%1" \
91 :"d" (x),"m" (*__ptr(ptr)) : "memory")
93 #define get_user(x, ptr) \
96 typeof(x) __gu_val = 0; \
97 switch (sizeof(*(ptr))) { \
99 __get_user_asm(__gu_err, __gu_val, ptr, b, "=d"); \
102 __get_user_asm(__gu_err, __gu_val, ptr, w, "=r"); \
105 __get_user_asm(__gu_err, __gu_val, ptr, l, "=r"); \
108 memcpy((void *) &__gu_val, ptr, sizeof (*(ptr))); \
112 __gu_err = __get_user_bad(); \
115 (x) = (typeof(*(ptr))) __gu_val; \
118 #define __get_user(x, ptr) get_user(x, ptr)
120 extern int __get_user_bad(void);
122 #define __get_user_asm(err,x,ptr,bwl,reg) \
123 __asm__ ("move" #bwl " %1,%0" \
127 #define copy_from_user(to, from, n) (memcpy(to, from, n), 0)
128 #define copy_to_user(to, from, n) (memcpy(to, from, n), 0)
130 #define __copy_from_user(to, from, n) copy_from_user(to, from, n)
131 #define __copy_to_user(to, from, n) copy_to_user(to, from, n)
132 #define __copy_to_user_inatomic __copy_to_user
133 #define __copy_from_user_inatomic __copy_from_user
136 * Copy a null terminated string from userspace.
140 strncpy_from_user(char *dst, const char *src, long count)
143 strncpy(dst, src, count);
144 for (tmp = dst; *tmp && count > 0; tmp++, count--)
146 return(tmp - dst); /* DAVIDM should we count a NUL ? check getname */
150 * Return the size of a string (including the ending 0)
152 * Return 0 on exception, a value greater than N if too long
154 static inline long strnlen_user(const char *src, long n)
156 return(strlen(src) + 1); /* DAVIDM make safer */
159 #define strlen_user(str) strnlen_user(str, 32767)
165 static inline unsigned long
166 __clear_user(void *to, unsigned long n)
172 #define clear_user(to,n) __clear_user(to,n)
174 #endif /* _M68KNOMMU_UACCESS_H */