uaccess.h

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#ifndef __H8300_UACCESS_H
#define __H8300_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

/* We let the MMU do all checking */
#define access_ok(type, addr, size) __access_ok((unsigned long)addr,size)
static inline int __access_ok(unsigned long addr, unsigned long size)
{
#define RANGE_CHECK_OK(addr, size, lower, upper) \
    (((addr) >= (lower)) && (((addr) + (size)) < (upper)))

    extern unsigned long _ramend;
    return(RANGE_CHECK_OK(addr, size, 0L, (unsigned long)&_ramend));
}

/*
 * 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:                     \
    case 2:                     \
    case 4:                     \
    *(ptr) = (__pu_val);                    \
    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))

/*
 * 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 get_user(x, ptr)                    \
({                              \
    int __gu_err = 0;                       \
    typeof(*(ptr)) __gu_val = *ptr;             \
    switch (sizeof(*(ptr))) {                   \
    case 1:                         \
    case 2:                         \
    case 4:                         \
    case 8:                             \
    break;                          \
    default:                            \
    __gu_err = __get_user_bad();                \
    break;                          \
    }                               \
    (x) = __gu_val;                     \
    __gu_err;                           \
})
#define __get_user(x, ptr) get_user(x, ptr)

extern int __get_user_bad(void);

#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    clear_user

#endif /* _H8300_UACCESS_H */