xref: /qemu/hw/virtio/vhost-shadow-virtqueue.c (revision 10857ec0ad5d201d524d20b477da1cf3f7f4a3b0)

/*
 * vhost shadow virtqueue
 *
 * SPDX-FileCopyrightText: Red Hat, Inc. 2021
 * SPDX-FileContributor: Author: Eugenio Pérez <eperezma@redhat.com>
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

#include "qemu/osdep.h"
#include "hw/virtio/vhost-shadow-virtqueue.h"

#include "qemu/error-report.h"

/**
 * Creates vhost shadow virtqueue, and instructs the vhost device to use the
 * shadow methods and file descriptors.
 *
 * Returns the new virtqueue or NULL.
 *
 * In case of error, reason is reported through error_report.
 */
VhostShadowVirtqueue *vhost_svq_new(void)
{
    g_autofree VhostShadowVirtqueue *svq = g_new0(VhostShadowVirtqueue, 1);
    int r;

    r = event_notifier_init(&svq->hdev_kick, 0);
    if (r != 0) {
        error_report("Couldn't create kick event notifier: %s (%d)",
                     g_strerror(errno), errno);
        goto err_init_hdev_kick;
    }

    r = event_notifier_init(&svq->hdev_call, 0);
    if (r != 0) {
        error_report("Couldn't create call event notifier: %s (%d)",
                     g_strerror(errno), errno);
        goto err_init_hdev_call;
    }

    return g_steal_pointer(&svq);

err_init_hdev_call:
    event_notifier_cleanup(&svq->hdev_kick);

err_init_hdev_kick:
    return NULL;
}

/**
 * Free the resources of the shadow virtqueue.
 *
 * @pvq: gpointer to SVQ so it can be used by autofree functions.
 */
void vhost_svq_free(gpointer pvq)
{
    VhostShadowVirtqueue *vq = pvq;
    event_notifier_cleanup(&vq->hdev_kick);
    event_notifier_cleanup(&vq->hdev_call);
    g_free(vq);
}