input-compat.c

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/*
 * 32bit compatibility wrappers for the input subsystem.
 *
 * Very heavily based on evdev.c - Copyright (c) 1999-2002 Vojtech Pavlik
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published by
 * the Free Software Foundation.
 */

#include <linux/export.h>
#include <asm/uaccess.h>
#include "input-compat.h"

#ifdef CONFIG_COMPAT

int input_event_from_user(const char __user *buffer,
              struct input_event *event)
{
    if (INPUT_COMPAT_TEST && !COMPAT_USE_64BIT_TIME) {
        struct input_event_compat compat_event;

        if (copy_from_user(&compat_event, buffer,
                   sizeof(struct input_event_compat)))
            return -EFAULT;

        event->time.tv_sec = compat_event.time.tv_sec;
        event->time.tv_usec = compat_event.time.tv_usec;
        event->type = compat_event.type;
        event->code = compat_event.code;
        event->value = compat_event.value;

    } else {
        if (copy_from_user(event, buffer, sizeof(struct input_event)))
            return -EFAULT;
    }

    return 0;
}

int input_event_to_user(char __user *buffer,
            const struct input_event *event)
{
    if (INPUT_COMPAT_TEST && !COMPAT_USE_64BIT_TIME) {
        struct input_event_compat compat_event;

        compat_event.time.tv_sec = event->time.tv_sec;
        compat_event.time.tv_usec = event->time.tv_usec;
        compat_event.type = event->type;
        compat_event.code = event->code;
        compat_event.value = event->value;

        if (copy_to_user(buffer, &compat_event,
                 sizeof(struct input_event_compat)))
            return -EFAULT;

    } else {
        if (copy_to_user(buffer, event, sizeof(struct input_event)))
            return -EFAULT;
    }

    return 0;
}

int input_ff_effect_from_user(const char __user *buffer, size_t size,
                  struct ff_effect *effect)
{
    if (INPUT_COMPAT_TEST) {
        struct ff_effect_compat *compat_effect;

        if (size != sizeof(struct ff_effect_compat))
            return -EINVAL;

        /*
         * It so happens that the pointer which needs to be changed
         * is the last field in the structure, so we can retrieve the
         * whole thing and replace just the pointer.
         */
        compat_effect = (struct ff_effect_compat *)effect;

        if (copy_from_user(compat_effect, buffer,
                   sizeof(struct ff_effect_compat)))
            return -EFAULT;

        if (compat_effect->type == FF_PERIODIC &&
            compat_effect->u.periodic.waveform == FF_CUSTOM)
            effect->u.periodic.custom_data =
                compat_ptr(compat_effect->u.periodic.custom_data);
    } else {
        if (size != sizeof(struct ff_effect))
            return -EINVAL;

        if (copy_from_user(effect, buffer, sizeof(struct ff_effect)))
            return -EFAULT;
    }

    return 0;
}

#else

int input_event_from_user(const char __user *buffer,
             struct input_event *event)
{
    if (copy_from_user(event, buffer, sizeof(struct input_event)))
        return -EFAULT;

    return 0;
}

int input_event_to_user(char __user *buffer,
            const struct input_event *event)
{
    if (copy_to_user(buffer, event, sizeof(struct input_event)))
        return -EFAULT;

    return 0;
}

int input_ff_effect_from_user(const char __user *buffer, size_t size,
                  struct ff_effect *effect)
{
    if (size != sizeof(struct ff_effect))
        return -EINVAL;

    if (copy_from_user(effect, buffer, sizeof(struct ff_effect)))
        return -EFAULT;

    return 0;
}

#endif /* CONFIG_COMPAT */

EXPORT_SYMBOL_GPL(input_event_from_user);
EXPORT_SYMBOL_GPL(input_event_to_user);
EXPORT_SYMBOL_GPL(input_ff_effect_from_user);