qemu/hw/virtio/vhost-shadow-virtqueue.h
Eugenio Pérez dafb34c992 virtio: Add vhost_svq_get_vring_addr
It reports the shadow virtqueue address from qemu virtual address space.

Since this will be different from the guest's vaddr, but the device can
access it, SVQ takes special care about its alignment & lack of garbage
data. It assumes that IOMMU will work in host_page_size ranges for that.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Jason Wang <jasowang@redhat.com>
2022-03-15 13:57:44 +08:00

57 lines
1.8 KiB
C

/*
* 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
*/
#ifndef VHOST_SHADOW_VIRTQUEUE_H
#define VHOST_SHADOW_VIRTQUEUE_H
#include "qemu/event_notifier.h"
#include "hw/virtio/virtio.h"
#include "standard-headers/linux/vhost_types.h"
/* Shadow virtqueue to relay notifications */
typedef struct VhostShadowVirtqueue {
/* Shadow vring */
struct vring vring;
/* Shadow kick notifier, sent to vhost */
EventNotifier hdev_kick;
/* Shadow call notifier, sent to vhost */
EventNotifier hdev_call;
/*
* Borrowed virtqueue's guest to host notifier. To borrow it in this event
* notifier allows to recover the VhostShadowVirtqueue from the event loop
* easily. If we use the VirtQueue's one, we don't have an easy way to
* retrieve VhostShadowVirtqueue.
*
* So shadow virtqueue must not clean it, or we would lose VirtQueue one.
*/
EventNotifier svq_kick;
/* Guest's call notifier, where the SVQ calls guest. */
EventNotifier svq_call;
} VhostShadowVirtqueue;
bool vhost_svq_valid_features(uint64_t features, Error **errp);
void vhost_svq_set_svq_kick_fd(VhostShadowVirtqueue *svq, int svq_kick_fd);
void vhost_svq_set_svq_call_fd(VhostShadowVirtqueue *svq, int call_fd);
void vhost_svq_get_vring_addr(const VhostShadowVirtqueue *svq,
struct vhost_vring_addr *addr);
size_t vhost_svq_driver_area_size(const VhostShadowVirtqueue *svq);
size_t vhost_svq_device_area_size(const VhostShadowVirtqueue *svq);
void vhost_svq_stop(VhostShadowVirtqueue *svq);
VhostShadowVirtqueue *vhost_svq_new(void);
void vhost_svq_free(gpointer vq);
G_DEFINE_AUTOPTR_CLEANUP_FUNC(VhostShadowVirtqueue, vhost_svq_free);
#endif