/* SPDX-License-Identifier: GPL-2.0 */
/* 
 * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
 * Copyright (C) 2015 Richard Weinberger (richard@nod.at)
 */

#ifndef __UM_UACCESS_H
#define __UM_UACCESS_H

#include <asm/elf.h>
#include <linux/unaligned.h>
#include <sysdep/faultinfo.h>

#define __under_task_size(addr, size) \
        (((unsigned long) (addr) < TASK_SIZE) && \
         (((unsigned long) (addr) + (size)) < TASK_SIZE))

#define __addr_range_nowrap(addr, size) \
        ((unsigned long) (addr) <= ((unsigned long) (addr) + (size)))

extern unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n);
extern unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n);
extern unsigned long __clear_user(void __user *mem, unsigned long len);
static inline int __access_ok(const void __user *ptr, unsigned long size);

/* Teach asm-generic/uaccess.h that we have C functions for these. */
#define __access_ok __access_ok
#define __clear_user __clear_user

#define INLINE_COPY_FROM_USER
#define INLINE_COPY_TO_USER

#include <asm-generic/uaccess.h>

static inline int __access_ok(const void __user *ptr, unsigned long size)
{
        unsigned long addr = (unsigned long)ptr;
        return __addr_range_nowrap(addr, size) && __under_task_size(addr, size);
}

#define __get_kernel_nofault(dst, src, type, err_label)                 \
do {                                                                    \
        int __faulted;                                                  \
                                                                        \
        ___backtrack_faulted(__faulted);                                \
        if (__faulted) {                                                \
                *((type *)dst) = (type) 0;                              \
                goto err_label;                                         \
        }                                                               \
        *((type *)dst) = get_unaligned((type *)(src));                  \
        barrier();                                                      \
        current->thread.segv_continue = NULL;                           \
} while (0)

#define __put_kernel_nofault(dst, src, type, err_label)                 \
do {                                                                    \
        int __faulted;                                                  \
                                                                        \
        ___backtrack_faulted(__faulted);                                \
        if (__faulted)                                                  \
                goto err_label;                                         \
        put_unaligned(*((type *)src), (type *)(dst));                   \
        barrier();                                                      \
        current->thread.segv_continue = NULL;                           \
} while (0)

#endif