/*-
 * Copyright (c) 2010 Isilon Systems, Inc.
 * Copyright (c) 2010 iX Systems, Inc.
 * Copyright (c) 2010 Panasas, Inc.
 * Copyright (c) 2015-2020 François Tigeot <ftigeot@wolfpond.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice unmodified, this list of conditions, and the following
 *    disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#ifndef _ASM_UACCESS_H_
#define _ASM_UACCESS_H_

#define get_user(_x, _p)        -copyin((_p), &(_x), sizeof(*(_p)))

static inline long
copy_to_user(void *to, const void *from, unsigned long n)
{
        if (copyout(from, to, n) != 0)
                return n;
        return 0;
}

static inline long
copy_from_user(void *to, const void *from, unsigned long n)
{
        if (copyin(from, to, n) != 0)
                return n;
        return 0;
}

static inline int
__copy_to_user(void *to, const void *from, unsigned len)
{
        if (copyout(from, to, len))
                return len;
        return 0;
}

static inline unsigned long
__copy_from_user(void *to, const void *from, unsigned len)
{
        if (copyin(from, to, len))
                return len;
        return 0;
}

static inline int
__copy_from_user_inatomic(void *dst, const void __user *src, unsigned size)
{
        if (copyin(src, dst, size))
                return size;
        return 0;
}

static inline int
__copy_to_user_inatomic(void __user *to, const void *from, unsigned n)
{
        return (copyout(from, to, n) != 0 ? n : 0);
}

static inline unsigned long
__copy_from_user_inatomic_nocache(void *to, const void __user *from,
    unsigned long n)
{
        /*
         * XXXKIB.  Equivalent Linux function is implemented using
         * MOVNTI for aligned moves.  For unaligned head and tail,
         * normal move is performed.  As such, it is not incorrect, if
         * only somewhat slower, to use normal copyin.  All uses
         * except shmem_pwrite_fast() have the destination mapped WC.
         */
        return ((copyin_nofault(__DECONST(void *, from), to, n) != 0 ? n : 0));
}

#define __get_user(x, ptr)      get_user((x), (ptr))

#define __put_user(value, uptr)                                         \
({                                                                      \
        __typeof(*(uptr)) __tmpval = (value);                           \
        __copy_to_user_inatomic((uptr), &__tmpval, sizeof(__tmpval));   \
})

#define put_user(_x, _p)        __put_user(_x, _p)

#define unsafe_put_user(x, ptr, err) do { \
        if (unlikely(__put_user(x, ptr))) \
                goto err; \
} while (0)

/* TODO: check me, taken from FreeBSD */
static inline int
access_ok(const void *uaddr, size_t len)
{
        uintptr_t saddr;
        uintptr_t eaddr;
        
        /* get start and end address */
        saddr = (uintptr_t)uaddr;
        eaddr = (uintptr_t)uaddr + len;
        
        /* verify addresses are valid for userspace */
        return ((saddr == eaddr) ||
            (eaddr > saddr && eaddr <= VM_MAX_USER_ADDRESS));
}

#define user_access_begin()
#define user_access_end()

#endif  /* _ASM_UACCESS_H_ */