virtio: add vhost support for virtio devices

This patch adds a get_vhost() callback function for VirtIODevices that
returns the device's corresponding vhost_dev structure, if the vhost
device is running. This patch also adds a vhost_started flag for
VirtIODevices.

Previously, a VirtIODevice wouldn't be able to tell if its corresponding
vhost device was active or not.

Signed-off-by: Jonah Palmer <jonah.palmer@oracle.com>
Message-Id: <1648819405-25696-3-git-send-email-jonah.palmer@oracle.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

6 files changed, 35 insertions, 1 deletions

diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c
index b875640..e513e4f 100644
--- a/hw/virtio/vhost-user-fs.c
+++ b/hw/virtio/vhost-user-fs.c
@@ -276,6 +276,12 @@ static void vuf_device_unrealize(DeviceState *dev)
     fs->vhost_dev.vqs = NULL;
 }
 
+static struct vhost_dev *vuf_get_vhost(VirtIODevice *vdev)
+{
+    VHostUserFS *fs = VHOST_USER_FS(vdev);
+    return &fs->vhost_dev;
+}
+
 static const VMStateDescription vuf_vmstate = {
     .name = "vhost-user-fs",
     .unmigratable = 1,
@@ -313,6 +319,7 @@ static void vuf_class_init(ObjectClass *klass, void *data)
     vdc->set_status = vuf_set_status;
     vdc->guest_notifier_mask = vuf_guest_notifier_mask;
     vdc->guest_notifier_pending = vuf_guest_notifier_pending;
+    vdc->get_vhost = vuf_get_vhost;
 }
 
 static const TypeInfo vuf_info = {
diff --git a/hw/virtio/vhost-user-rng.c b/hw/virtio/vhost-user-rng.c
index 08bccba..3a7bf8e 100644
--- a/hw/virtio/vhost-user-rng.c
+++ b/hw/virtio/vhost-user-rng.c
@@ -247,6 +247,12 @@ static void vu_rng_device_unrealize(DeviceState *dev)
     vhost_user_cleanup(&rng->vhost_user);
 }
 
+static struct vhost_dev *vu_rng_get_vhost(VirtIODevice *vdev)
+{
+    VHostUserRNG *rng = VHOST_USER_RNG(vdev);
+    return &rng->vhost_dev;
+}
+
 static const VMStateDescription vu_rng_vmstate = {
     .name = "vhost-user-rng",
     .unmigratable = 1,
@@ -272,6 +278,7 @@ static void vu_rng_class_init(ObjectClass *klass, void *data)
     vdc->set_status = vu_rng_set_status;
     vdc->guest_notifier_mask = vu_rng_guest_notifier_mask;
     vdc->guest_notifier_pending = vu_rng_guest_notifier_pending;
+    vdc->get_vhost = vu_rng_get_vhost;
 }
 
 static const TypeInfo vu_rng_info = {
diff --git a/hw/virtio/vhost-vsock-common.c b/hw/virtio/vhost-vsock-common.c
index ad5c8ff..7394818 100644
--- a/hw/virtio/vhost-vsock-common.c
+++ b/hw/virtio/vhost-vsock-common.c
@@ -258,6 +258,12 @@ void vhost_vsock_common_unrealize(VirtIODevice *vdev)
     virtio_cleanup(vdev);
 }
 
+static struct vhost_dev *vhost_vsock_common_get_vhost(VirtIODevice *vdev)
+{
+    VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
+    return &vvc->vhost_dev;
+}
+
 static Property vhost_vsock_common_properties[] = {
     DEFINE_PROP_ON_OFF_AUTO("seqpacket", VHostVSockCommon, seqpacket,
                             ON_OFF_AUTO_AUTO),
@@ -273,6 +279,7 @@ static void vhost_vsock_common_class_init(ObjectClass *klass, void *data)
     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
     vdc->guest_notifier_mask = vhost_vsock_common_guest_notifier_mask;
     vdc->guest_notifier_pending = vhost_vsock_common_guest_notifier_pending;
+    vdc->get_vhost = vhost_vsock_common_get_vhost;
 }
 
 static const TypeInfo vhost_vsock_common_info = {
diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
index 2bc72c2..dd3263d 100644
--- a/hw/virtio/vhost.c
+++ b/hw/virtio/vhost.c
@@ -1738,6 +1738,7 @@ int vhost_dev_start(struct vhost_dev *hdev, VirtIODevice *vdev)
     /* should only be called after backend is connected */
     assert(hdev->vhost_ops);
 
+    vdev->vhost_started = true;
     hdev->started = true;
     hdev->vdev = vdev;
 
@@ -1810,7 +1811,7 @@ fail_vq:
 
 fail_mem:
 fail_features:
-
+    vdev->vhost_started = false;
     hdev->started = false;
     return r;
 }
@@ -1841,6 +1842,7 @@ void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev)
     }
     vhost_log_put(hdev, true);
     hdev->started = false;
+    vdev->vhost_started = false;
     hdev->vdev = NULL;
 }
 
diff --git a/hw/virtio/virtio-crypto.c b/hw/virtio/virtio-crypto.c
index df9adb2..c3829e7 100644
--- a/hw/virtio/virtio-crypto.c
+++ b/hw/virtio/virtio-crypto.c
@@ -961,6 +961,15 @@ static bool virtio_crypto_guest_notifier_pending(VirtIODevice *vdev, int idx)
     return cryptodev_vhost_virtqueue_pending(vdev, queue, idx);
 }
 
+static struct vhost_dev *virtio_crypto_get_vhost(VirtIODevice *vdev)
+{
+    VirtIOCrypto *vcrypto = VIRTIO_CRYPTO(vdev);
+    CryptoDevBackend *b = vcrypto->cryptodev;
+    CryptoDevBackendClient *cc = b->conf.peers.ccs[0];
+    CryptoDevBackendVhost *vhost_crypto = cryptodev_get_vhost(cc, b, 0);
+    return &vhost_crypto->dev;
+}
+
 static void virtio_crypto_class_init(ObjectClass *klass, void *data)
 {
     DeviceClass *dc = DEVICE_CLASS(klass);
@@ -977,6 +986,7 @@ static void virtio_crypto_class_init(ObjectClass *klass, void *data)
     vdc->set_status = virtio_crypto_set_status;
     vdc->guest_notifier_mask = virtio_crypto_guest_notifier_mask;
     vdc->guest_notifier_pending = virtio_crypto_guest_notifier_pending;
+    vdc->get_vhost = virtio_crypto_get_vhost;
 }
 
 static void virtio_crypto_instance_init(Object *obj)
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
index 7f9fcfd..5d607ae 100644
--- a/hw/virtio/virtio.c
+++ b/hw/virtio/virtio.c
@@ -3271,6 +3271,7 @@ void virtio_init(VirtIODevice *vdev, uint16_t device_id, size_t config_size)
 
     vdev->start_on_kick = false;
     vdev->started = false;
+    vdev->vhost_started = false;
     vdev->device_id = device_id;
     vdev->status = 0;
     qatomic_set(&vdev->isr, 0);