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#ifndef __M68KNOMMU_UACCESS_H
#define __M68KNOMMU_UACCESS_H
/*
* User space memory access functions
*/
#include <linux/sched.h>
#include <linux/mm.h>
#include <linux/string.h>
#include <asm/segment.h>
#define VERIFY_READ 0
#define VERIFY_WRITE 1
#define access_ok(type,addr,size) _access_ok((unsigned long)(addr),(size))
/*
* It is not enough to just have access_ok check for a real RAM address.
* This would disallow the case of code/ro-data running XIP in flash/rom.
* Ideally we would check the possible flash ranges too, but that is
* currently not so easy.
*/
static inline int _access_ok(unsigned long addr, unsigned long size)
{
return 1;
}
/*
* 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;
};
/* Returns 0 if exception not found and fixup otherwise. */
extern unsigned long search_exception_table(unsigned long);
/*
* 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) \
({ \
int __pu_err = 0; \
typeof(*(ptr)) __pu_val = (x); \
switch (sizeof (*(ptr))) { \
case 1: \
__put_user_asm(__pu_err, __pu_val, ptr, b); \
break; \
case 2: \
__put_user_asm(__pu_err, __pu_val, ptr, w); \
break; \
case 4: \
__put_user_asm(__pu_err, __pu_val, ptr, l); \
break; \
case 8: \
memcpy(ptr, &__pu_val, sizeof (*(ptr))); \
break; \
default: \
__pu_err = __put_user_bad(); \
break; \
} \
__pu_err; \
})
#define __put_user(x, ptr) put_user(x, ptr)
extern int __put_user_bad(void);
/*
* Tell gcc we read from memory instead of writing: this is because
* we do not write to any memory gcc knows about, so there are no
* aliasing issues.
*/
#define __ptr(x) ((unsigned long *)(x))
#define __put_user_asm(err,x,ptr,bwl) \
__asm__ ("move" #bwl " %0,%1" \
: /* no outputs */ \
:"d" (x),"m" (*__ptr(ptr)) : "memory")
#define get_user(x, ptr) \
({ \
int __gu_err = 0; \
typeof(x) __gu_val = 0; \
switch (sizeof(*(ptr))) { \
case 1: \
__get_user_asm(__gu_err, __gu_val, ptr, b, "=d"); \
break; \
case 2: \
__get_user_asm(__gu_err, __gu_val, ptr, w, "=r"); \
break; \
case 4: \
__get_user_asm(__gu_err, __gu_val, ptr, l, "=r"); \
break; \
case 8: \
memcpy((void *) &__gu_val, ptr, sizeof (*(ptr))); \
break; \
default: \
__gu_val = 0; \
__gu_err = __get_user_bad(); \
break; \
} \
(x) = (typeof(*(ptr))) __gu_val; \
__gu_err; \
})
#define __get_user(x, ptr) get_user(x, ptr)
extern int __get_user_bad(void);
#define __get_user_asm(err,x,ptr,bwl,reg) \
__asm__ ("move" #bwl " %1,%0" \
: "=d" (x) \
: "m" (*__ptr(ptr)))
#define copy_from_user(to, from, n) (memcpy(to, from, n), 0)
#define copy_to_user(to, from, n) (memcpy(to, from, n), 0)
#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)
#define __copy_to_user_inatomic __copy_to_user
#define __copy_from_user_inatomic __copy_from_user
#define copy_to_user_ret(to,from,n,retval) ({ if (copy_to_user(to,from,n)) return retval; })
#define copy_from_user_ret(to,from,n,retval) ({ if (copy_from_user(to,from,n)) return retval; })
/*
* Copy a null terminated string from userspace.
*/
static inline long
strncpy_from_user(char *dst, const char *src, long count)
{
char *tmp;
strncpy(dst, src, count);
for (tmp = dst; *tmp && count > 0; tmp++, count--)
;
return(tmp - dst); /* DAVIDM should we count a NUL ? check getname */
}
/*
* Return the size of a string (including the ending 0)
*
* Return 0 on exception, a value greater than N if too long
*/
static inline long strnlen_user(const char *src, long n)
{
return(strlen(src) + 1); /* DAVIDM make safer */
}
#define strlen_user(str) strnlen_user(str, 32767)
/*
* Zero Userspace
*/
static inline unsigned long
__clear_user(void *to, unsigned long n)
{
memset(to, 0, n);
return 0;
}
#define clear_user(to,n) __clear_user(to,n)
#endif /* _M68KNOMMU_UACCESS_H */
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