/*
 * Virtio RNG Support
 *
 * Copyright Red Hat, Inc. 2012
 * Copyright Amit Shah <amit.shah@redhat.com>
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or
 * (at your option) any later version.  See the COPYING file in the
 * top-level directory.
 */

#ifndef _QEMU_VIRTIO_RNG_H
#define _QEMU_VIRTIO_RNG_H

#include "qemu/rng.h"
#include "qemu/rng-random.h"

/* The Virtio ID for the virtio rng device */
#define VIRTIO_ID_RNG    4

struct VirtIORNGConf {
    RngBackend *rng;
    uint64_t max_bytes;
    uint32_t period_ms;
    RndRandom *default_backend;
};

typedef struct VirtIORNG {
    VirtIODevice vdev;

    DeviceState *qdev;

    /* Only one vq - guest puts buffer(s) on it when it needs entropy */
    VirtQueue *vq;

    VirtIORNGConf *conf;

    RngBackend *rng;

    /* We purposefully don't migrate this state.  The quota will reset on the
     * destination as a result.  Rate limiting is host state, not guest state.
     */
    QEMUTimer *rate_limit_timer;
    int64_t quota_remaining;
} VirtIORNG;

#endif