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Re: [PATCH v2 2/5] vhost: introduce wrappers to set guest notifiers for
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From: |
Dima Stepanov |
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Subject: |
Re: [PATCH v2 2/5] vhost: introduce wrappers to set guest notifiers for virtio device |
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Date: |
Mon, 11 May 2020 11:55:41 +0300 |
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User-agent: |
Mutt/1.5.24 (2015-08-30) |
On Mon, May 11, 2020 at 11:03:01AM +0800, Jason Wang wrote:
>
> On 2020/4/30 下午9:36, Dima Stepanov wrote:
> >Introduce new wrappers to set/reset guest notifiers for the virtio
> >device in the vhost device module:
> > vhost_dev_assign_guest_notifiers
> > ->set_guest_notifiers(..., ..., true);
> > vhost_dev_drop_guest_notifiers
> > ->set_guest_notifiers(..., ..., false);
> >This is a preliminary step to refactor code,
>
>
> Maybe I miss something, I don't see any add-on patch to modify the new
> wrapper in this series?
Hi, in fact the next 3/5 patch:
"[PATCH v2 3/5] vhost-user-blk: add mechanism to track the guest
notifiers init state"
is about using these wrappers. But disregard it, i decided to follow
Raphael suggestion. So we will fix the vhost-user-blk case first, so i
will not introduce these wrappers. And the code will be more easier to
read and straightforward.
I will send v3 as soon as we decide what to do with the migration fix
in this patchset.
No other comments mixed in below.
>
>
> > so the set_guest_notifiers
> >methods could be called based on the vhost device state.
> >Update all vhost used devices to use these wrappers instead of direct
> >method call.
> >
> >Signed-off-by: Dima Stepanov <address@hidden>
> >---
> > backends/cryptodev-vhost.c | 26 +++++++++++++++-----------
> > backends/vhost-user.c | 16 +++++-----------
> > hw/block/vhost-user-blk.c | 15 +++++----------
> > hw/net/vhost_net.c | 30 +++++++++++++++++-------------
> > hw/scsi/vhost-scsi-common.c | 15 +++++----------
> > hw/virtio/vhost-user-fs.c | 17 +++++++----------
> > hw/virtio/vhost-vsock.c | 18 ++++++++----------
> > hw/virtio/vhost.c | 38 ++++++++++++++++++++++++++++++++++++++
> > hw/virtio/virtio.c | 13 +++++++++++++
> > include/hw/virtio/vhost.h | 4 ++++
> > include/hw/virtio/virtio.h | 1 +
> > 11 files changed, 118 insertions(+), 75 deletions(-)
> >
> >diff --git a/backends/cryptodev-vhost.c b/backends/cryptodev-vhost.c
> >index 8337c9a..4522195 100644
> >--- a/backends/cryptodev-vhost.c
> >+++ b/backends/cryptodev-vhost.c
> >@@ -169,16 +169,13 @@ vhost_set_vring_enable(CryptoDevBackendClient *cc,
> > int cryptodev_vhost_start(VirtIODevice *dev, int total_queues)
> > {
> > VirtIOCrypto *vcrypto = VIRTIO_CRYPTO(dev);
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
> >- VirtioBusState *vbus = VIRTIO_BUS(qbus);
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus);
> > int r, e;
> > int i;
> > CryptoDevBackend *b = vcrypto->cryptodev;
> > CryptoDevBackendVhost *vhost_crypto;
> > CryptoDevBackendClient *cc;
> >- if (!k->set_guest_notifiers) {
> >+ if (!virtio_device_guest_notifiers_initialized(dev)) {
> > error_report("binding does not support guest notifiers");
> > return -ENOSYS;
> > }
> >@@ -198,9 +195,13 @@ int cryptodev_vhost_start(VirtIODevice *dev, int
> >total_queues)
> > }
> > }
> >- r = k->set_guest_notifiers(qbus->parent, total_queues, true);
> >+ /*
> >+ * Since all the states are handled by one vhost device,
> >+ * use the first one in array.
> >+ */
> >+ vhost_crypto = cryptodev_get_vhost(b->conf.peers.ccs[0], b, 0);
> >+ r = vhost_dev_assign_guest_notifiers(&vhost_crypto->dev, dev,
> >total_queues);
> > if (r < 0) {
> >- error_report("error binding guest notifier: %d", -r);
> > goto err;
> > }
> >@@ -232,7 +233,8 @@ err_start:
> > vhost_crypto = cryptodev_get_vhost(cc, b, i);
> > cryptodev_vhost_stop_one(vhost_crypto, dev);
> > }
> >- e = k->set_guest_notifiers(qbus->parent, total_queues, false);
> >+ vhost_crypto = cryptodev_get_vhost(b->conf.peers.ccs[0], b, 0);
> >+ e = vhost_dev_drop_guest_notifiers(&vhost_crypto->dev, dev,
> >total_queues);
> > if (e < 0) {
> > error_report("vhost guest notifier cleanup failed: %d", e);
> > }
> >@@ -242,9 +244,6 @@ err:
> > void cryptodev_vhost_stop(VirtIODevice *dev, int total_queues)
> > {
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
> >- VirtioBusState *vbus = VIRTIO_BUS(qbus);
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus);
> > VirtIOCrypto *vcrypto = VIRTIO_CRYPTO(dev);
> > CryptoDevBackend *b = vcrypto->cryptodev;
> > CryptoDevBackendVhost *vhost_crypto;
> >@@ -259,7 +258,12 @@ void cryptodev_vhost_stop(VirtIODevice *dev, int
> >total_queues)
> > cryptodev_vhost_stop_one(vhost_crypto, dev);
> > }
> >- r = k->set_guest_notifiers(qbus->parent, total_queues, false);
> >+ /*
> >+ * Since all the states are handled by one vhost device,
> >+ * use the first one in array.
> >+ */
> >+ vhost_crypto = cryptodev_get_vhost(b->conf.peers.ccs[0], b, 0);
> >+ r = vhost_dev_drop_guest_notifiers(&vhost_crypto->dev, dev,
> >total_queues);
> > if (r < 0) {
> > error_report("vhost guest notifier cleanup failed: %d", r);
> > }
> >diff --git a/backends/vhost-user.c b/backends/vhost-user.c
> >index 2bf3406..e116bc6 100644
> >--- a/backends/vhost-user.c
> >+++ b/backends/vhost-user.c
> >@@ -60,15 +60,13 @@ vhost_user_backend_dev_init(VhostUserBackend *b,
> >VirtIODevice *vdev,
> > void
> > vhost_user_backend_start(VhostUserBackend *b)
> > {
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(b->vdev)));
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> > int ret, i ;
> > if (b->started) {
> > return;
> > }
> >- if (!k->set_guest_notifiers) {
> >+ if (!virtio_device_guest_notifiers_initialized(b->vdev)) {
> > error_report("binding does not support guest notifiers");
> > return;
> > }
> >@@ -78,9 +76,8 @@ vhost_user_backend_start(VhostUserBackend *b)
> > return;
> > }
> >- ret = k->set_guest_notifiers(qbus->parent, b->dev.nvqs, true);
> >+ ret = vhost_dev_assign_guest_notifiers(&b->dev, b->vdev, b->dev.nvqs);
> > if (ret < 0) {
> >- error_report("Error binding guest notifier");
> > goto err_host_notifiers;
> > }
> >@@ -104,7 +101,7 @@ vhost_user_backend_start(VhostUserBackend *b)
> > return;
> > err_guest_notifiers:
> >- k->set_guest_notifiers(qbus->parent, b->dev.nvqs, false);
> >+ vhost_dev_drop_guest_notifiers(&b->dev, b->vdev, b->dev.nvqs);
> > err_host_notifiers:
> > vhost_dev_disable_notifiers(&b->dev, b->vdev);
> > }
> >@@ -112,8 +109,6 @@ err_host_notifiers:
> > void
> > vhost_user_backend_stop(VhostUserBackend *b)
> > {
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(b->vdev)));
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> > int ret = 0;
> > if (!b->started) {
> >@@ -122,9 +117,8 @@ vhost_user_backend_stop(VhostUserBackend *b)
> > vhost_dev_stop(&b->dev, b->vdev);
> >- if (k->set_guest_notifiers) {
> >- ret = k->set_guest_notifiers(qbus->parent,
> >- b->dev.nvqs, false);
> >+ if (virtio_device_guest_notifiers_initialized(b->vdev)) {
> >+ ret = vhost_dev_drop_guest_notifiers(&b->dev, b->vdev, b->dev.nvqs);
> > if (ret < 0) {
> > error_report("vhost guest notifier cleanup failed: %d", ret);
> > }
> >diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
> >index 17df533..70d7842 100644
> >--- a/hw/block/vhost-user-blk.c
> >+++ b/hw/block/vhost-user-blk.c
> >@@ -109,11 +109,9 @@ const VhostDevConfigOps blk_ops = {
> > static int vhost_user_blk_start(VirtIODevice *vdev)
> > {
> > VHostUserBlk *s = VHOST_USER_BLK(vdev);
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> > int i, ret;
> >- if (!k->set_guest_notifiers) {
> >+ if (!virtio_device_guest_notifiers_initialized(vdev)) {
> > error_report("binding does not support guest notifiers");
> > return -ENOSYS;
> > }
> >@@ -124,9 +122,8 @@ static int vhost_user_blk_start(VirtIODevice *vdev)
> > return ret;
> > }
> >- ret = k->set_guest_notifiers(qbus->parent, s->dev.nvqs, true);
> >+ ret = vhost_dev_assign_guest_notifiers(&s->dev, vdev, s->dev.nvqs);
> > if (ret < 0) {
> >- error_report("Error binding guest notifier: %d", -ret);
> > goto err_host_notifiers;
> > }
> >@@ -163,7 +160,7 @@ static int vhost_user_blk_start(VirtIODevice *vdev)
> > return ret;
> > err_guest_notifiers:
> >- k->set_guest_notifiers(qbus->parent, s->dev.nvqs, false);
> >+ vhost_dev_drop_guest_notifiers(&s->dev, vdev, s->dev.nvqs);
> > err_host_notifiers:
> > vhost_dev_disable_notifiers(&s->dev, vdev);
> > return ret;
> >@@ -172,17 +169,15 @@ err_host_notifiers:
> > static void vhost_user_blk_stop(VirtIODevice *vdev)
> > {
> > VHostUserBlk *s = VHOST_USER_BLK(vdev);
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> > int ret;
> >- if (!k->set_guest_notifiers) {
> >+ if (!virtio_device_guest_notifiers_initialized(vdev)) {
> > return;
> > }
> > vhost_dev_stop(&s->dev, vdev);
> >- ret = k->set_guest_notifiers(qbus->parent, s->dev.nvqs, false);
> >+ ret = vhost_dev_drop_guest_notifiers(&s->dev, vdev, s->dev.nvqs);
> > if (ret < 0) {
> > error_report("vhost guest notifier cleanup failed: %d", ret);
> > return;
> >diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
> >index 6b82803..c13b444 100644
> >--- a/hw/net/vhost_net.c
> >+++ b/hw/net/vhost_net.c
> >@@ -303,19 +303,15 @@ static void vhost_net_stop_one(struct vhost_net *net,
> > int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
> > int total_queues)
> > {
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
> >- VirtioBusState *vbus = VIRTIO_BUS(qbus);
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus);
> >+ struct vhost_net *net;
> > int r, e, i;
> >- if (!k->set_guest_notifiers) {
> >+ if (!virtio_device_guest_notifiers_initialized(dev)) {
> > error_report("binding does not support guest notifiers");
> > return -ENOSYS;
> > }
> > for (i = 0; i < total_queues; i++) {
> >- struct vhost_net *net;
> >-
> > net = get_vhost_net(ncs[i].peer);
> > vhost_net_set_vq_index(net, i * 2);
> >@@ -328,9 +324,13 @@ int vhost_net_start(VirtIODevice *dev, NetClientState
> >*ncs,
> > }
> > }
> >- r = k->set_guest_notifiers(qbus->parent, total_queues * 2, true);
> >+ /*
> >+ * Since all the states are handled by one vhost_net device,
> >+ * use the first one in array.
> >+ */
>
>
> This comment is confusing, kernel vhost-net backends will use all its peers.
>
>
> >+ net = get_vhost_net(ncs[0].peer);
> >+ r = vhost_dev_assign_guest_notifiers(&net->dev, dev, total_queues * 2);
> > if (r < 0) {
> >- error_report("Error binding guest notifier: %d", -r);
> > goto err;
> > }
> >@@ -357,7 +357,8 @@ err_start:
> > while (--i >= 0) {
> > vhost_net_stop_one(get_vhost_net(ncs[i].peer), dev);
> > }
> >- e = k->set_guest_notifiers(qbus->parent, total_queues * 2, false);
> >+ net = get_vhost_net(ncs[0].peer);
> >+ e = vhost_dev_drop_guest_notifiers(&net->dev, dev, total_queues * 2);
> > if (e < 0) {
> > fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", e);
> > fflush(stderr);
> >@@ -369,16 +370,19 @@ err:
> > void vhost_net_stop(VirtIODevice *dev, NetClientState *ncs,
> > int total_queues)
> > {
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(dev)));
> >- VirtioBusState *vbus = VIRTIO_BUS(qbus);
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(vbus);
> >+ struct vhost_net *net;
> > int i, r;
> > for (i = 0; i < total_queues; i++) {
> > vhost_net_stop_one(get_vhost_net(ncs[i].peer), dev);
> > }
> >- r = k->set_guest_notifiers(qbus->parent, total_queues * 2, false);
> >+ /*
> >+ * Since all the states are handled by one vhost_net device,
> >+ * use the first one in array.
> >+ */
> >+ net = get_vhost_net(ncs[0].peer);
> >+ r = vhost_dev_drop_guest_notifiers(&net->dev, dev, total_queues * 2);
> > if (r < 0) {
> > fprintf(stderr, "vhost guest notifier cleanup failed: %d\n", r);
> > fflush(stderr);
> >diff --git a/hw/scsi/vhost-scsi-common.c b/hw/scsi/vhost-scsi-common.c
> >index 8ec49d7..8f51ec0 100644
> >--- a/hw/scsi/vhost-scsi-common.c
> >+++ b/hw/scsi/vhost-scsi-common.c
> >@@ -29,10 +29,8 @@ int vhost_scsi_common_start(VHostSCSICommon *vsc)
> > {
> > int ret, i;
> > VirtIODevice *vdev = VIRTIO_DEVICE(vsc);
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> >- if (!k->set_guest_notifiers) {
> >+ if (!virtio_device_guest_notifiers_initialized(vdev)) {
> > error_report("binding does not support guest notifiers");
> > return -ENOSYS;
> > }
> >@@ -42,9 +40,8 @@ int vhost_scsi_common_start(VHostSCSICommon *vsc)
> > return ret;
> > }
> >- ret = k->set_guest_notifiers(qbus->parent, vsc->dev.nvqs, true);
> >+ ret = vhost_dev_assign_guest_notifiers(&vsc->dev, vdev, vsc->dev.nvqs);
> > if (ret < 0) {
> >- error_report("Error binding guest notifier");
> > goto err_host_notifiers;
> > }
> >@@ -66,7 +63,7 @@ int vhost_scsi_common_start(VHostSCSICommon *vsc)
> > return ret;
> > err_guest_notifiers:
> >- k->set_guest_notifiers(qbus->parent, vsc->dev.nvqs, false);
> >+ vhost_dev_drop_guest_notifiers(&vsc->dev, vdev, vsc->dev.nvqs);
> > err_host_notifiers:
> > vhost_dev_disable_notifiers(&vsc->dev, vdev);
> > return ret;
> >@@ -75,14 +72,12 @@ err_host_notifiers:
> > void vhost_scsi_common_stop(VHostSCSICommon *vsc)
> > {
> > VirtIODevice *vdev = VIRTIO_DEVICE(vsc);
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> > int ret = 0;
> > vhost_dev_stop(&vsc->dev, vdev);
> >- if (k->set_guest_notifiers) {
> >- ret = k->set_guest_notifiers(qbus->parent, vsc->dev.nvqs, false);
> >+ if (virtio_device_guest_notifiers_initialized(vdev)) {
> >+ ret = vhost_dev_drop_guest_notifiers(&vsc->dev, vdev,
> >vsc->dev.nvqs);
> > if (ret < 0) {
> > error_report("vhost guest notifier cleanup failed: %d",
> > ret);
> > }
> >diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c
> >index 6136768..6b101fc 100644
> >--- a/hw/virtio/vhost-user-fs.c
> >+++ b/hw/virtio/vhost-user-fs.c
> >@@ -38,12 +38,10 @@ static void vuf_get_config(VirtIODevice *vdev, uint8_t
> >*config)
> > static void vuf_start(VirtIODevice *vdev)
> > {
> > VHostUserFS *fs = VHOST_USER_FS(vdev);
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> > int ret;
> > int i;
> >- if (!k->set_guest_notifiers) {
> >+ if (!virtio_device_guest_notifiers_initialized(vdev)) {
> > error_report("binding does not support guest notifiers");
> > return;
> > }
> >@@ -54,9 +52,9 @@ static void vuf_start(VirtIODevice *vdev)
> > return;
> > }
> >- ret = k->set_guest_notifiers(qbus->parent, fs->vhost_dev.nvqs, true);
> >+ ret = vhost_dev_assign_guest_notifiers(&fs->vhost_dev, vdev,
> >+ fs->vhost_dev.nvqs);
> > if (ret < 0) {
> >- error_report("Error binding guest notifier: %d", -ret);
> > goto err_host_notifiers;
> > }
> >@@ -79,7 +77,7 @@ static void vuf_start(VirtIODevice *vdev)
> > return;
> > err_guest_notifiers:
> >- k->set_guest_notifiers(qbus->parent, fs->vhost_dev.nvqs, false);
> >+ vhost_dev_drop_guest_notifiers(&fs->vhost_dev, vdev,
> >fs->vhost_dev.nvqs);
> > err_host_notifiers:
> > vhost_dev_disable_notifiers(&fs->vhost_dev, vdev);
> > }
> >@@ -87,17 +85,16 @@ err_host_notifiers:
> > static void vuf_stop(VirtIODevice *vdev)
> > {
> > VHostUserFS *fs = VHOST_USER_FS(vdev);
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> > int ret;
> >- if (!k->set_guest_notifiers) {
> >+ if (!virtio_device_guest_notifiers_initialized(vdev)) {
> > return;
> > }
> > vhost_dev_stop(&fs->vhost_dev, vdev);
> >- ret = k->set_guest_notifiers(qbus->parent, fs->vhost_dev.nvqs, false);
> >+ ret = vhost_dev_drop_guest_notifiers(&fs->vhost_dev, vdev,
> >+ fs->vhost_dev.nvqs);
> > if (ret < 0) {
> > error_report("vhost guest notifier cleanup failed: %d", ret);
> > return;
> >diff --git a/hw/virtio/vhost-vsock.c b/hw/virtio/vhost-vsock.c
> >index 09b6b07..52489dd 100644
> >--- a/hw/virtio/vhost-vsock.c
> >+++ b/hw/virtio/vhost-vsock.c
> >@@ -75,12 +75,10 @@ static int vhost_vsock_set_running(VHostVSock *vsock,
> >int start)
> > static void vhost_vsock_start(VirtIODevice *vdev)
> > {
> > VHostVSock *vsock = VHOST_VSOCK(vdev);
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> > int ret;
> > int i;
> >- if (!k->set_guest_notifiers) {
> >+ if (!virtio_device_guest_notifiers_initialized(vdev)) {
> > error_report("binding does not support guest notifiers");
> > return;
> > }
> >@@ -91,9 +89,9 @@ static void vhost_vsock_start(VirtIODevice *vdev)
> > return;
> > }
> >- ret = k->set_guest_notifiers(qbus->parent, vsock->vhost_dev.nvqs, true);
> >+ ret = vhost_dev_assign_guest_notifiers(&vsock->vhost_dev,
> >+ vdev, vsock->vhost_dev.nvqs);
> > if (ret < 0) {
> >- error_report("Error binding guest notifier: %d", -ret);
> > goto err_host_notifiers;
> > }
> >@@ -123,7 +121,8 @@ static void vhost_vsock_start(VirtIODevice *vdev)
> > err_dev_start:
> > vhost_dev_stop(&vsock->vhost_dev, vdev);
> > err_guest_notifiers:
> >- k->set_guest_notifiers(qbus->parent, vsock->vhost_dev.nvqs, false);
> >+ vhost_dev_drop_guest_notifiers(&vsock->vhost_dev,
> >+ vdev, vsock->vhost_dev.nvqs);
> > err_host_notifiers:
> > vhost_dev_disable_notifiers(&vsock->vhost_dev, vdev);
> > }
> >@@ -131,11 +130,9 @@ err_host_notifiers:
> > static void vhost_vsock_stop(VirtIODevice *vdev)
> > {
> > VHostVSock *vsock = VHOST_VSOCK(vdev);
> >- BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >- VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> > int ret;
> >- if (!k->set_guest_notifiers) {
> >+ if (!virtio_device_guest_notifiers_initialized(vdev)) {
> > return;
> > }
> >@@ -147,7 +144,8 @@ static void vhost_vsock_stop(VirtIODevice *vdev)
> > vhost_dev_stop(&vsock->vhost_dev, vdev);
> >- ret = k->set_guest_notifiers(qbus->parent, vsock->vhost_dev.nvqs,
> >false);
> >+ ret = vhost_dev_drop_guest_notifiers(&vsock->vhost_dev,
> >+ vdev, vsock->vhost_dev.nvqs);
> > if (ret < 0) {
> > error_report("vhost guest notifier cleanup failed: %d", ret);
> > return;
> >diff --git a/hw/virtio/vhost.c b/hw/virtio/vhost.c
> >index 01ebe12..fa3da9c 100644
> >--- a/hw/virtio/vhost.c
> >+++ b/hw/virtio/vhost.c
> >@@ -1419,6 +1419,44 @@ void vhost_dev_disable_notifiers(struct vhost_dev
> >*hdev, VirtIODevice *vdev)
> > virtio_device_release_ioeventfd(vdev);
> > }
> >+/*
> >+ * Assign guest notifiers.
> >+ * Should be called after vhost_dev_enable_notifiers.
> >+ */
> >+int vhost_dev_assign_guest_notifiers(struct vhost_dev *hdev,
> >+ VirtIODevice *vdev, int nvqs)
> >+{
> >+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> >+ int ret;
> >+
> >+ ret = k->set_guest_notifiers(qbus->parent, nvqs, true);
> >+ if (ret < 0) {
> >+ error_report("Error binding guest notifier: %d", -ret);
> >+ }
> >+
> >+ return ret;
> >+}
> >+
> >+/*
> >+ * Drop guest notifiers.
> >+ * Should be called before vhost_dev_disable_notifiers.
> >+ */
> >+int vhost_dev_drop_guest_notifiers(struct vhost_dev *hdev,
> >+ VirtIODevice *vdev, int nvqs)
> >+{
>
>
> hdev is not used?
>
> Thanks
>
>
> >+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> >+ int ret;
> >+
> >+ ret = k->set_guest_notifiers(qbus->parent, nvqs, false);
> >+ if (ret < 0) {
> >+ error_report("Error reset guest notifier: %d", -ret);
> >+ }
> >+
> >+ return ret;
> >+}
> >+
> > /* Test and clear event pending status.
> > * Should be called after unmask to avoid losing events.
> > */
> >diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
> >index b6c8ef5..8a95618 100644
> >--- a/hw/virtio/virtio.c
> >+++ b/hw/virtio/virtio.c
> >@@ -3812,6 +3812,19 @@ bool virtio_device_ioeventfd_enabled(VirtIODevice
> >*vdev)
> > return virtio_bus_ioeventfd_enabled(vbus);
> > }
> >+/*
> >+ * Check if set_guest_notifiers() method is set by the init routine.
> >+ * Return true if yes, otherwise return false.
> >+ */
> >+bool virtio_device_guest_notifiers_initialized(VirtIODevice *vdev)
> >+{
> >+ BusState *qbus = BUS(qdev_get_parent_bus(DEVICE(vdev)));
> >+ VirtioBusClass *k = VIRTIO_BUS_GET_CLASS(qbus);
> >+
> >+ return k->set_guest_notifiers;
> >+}
> >+
> >+
> > static const TypeInfo virtio_device_info = {
> > .name = TYPE_VIRTIO_DEVICE,
> > .parent = TYPE_DEVICE,
> >diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h
> >index 085450c..4d0d2e2 100644
> >--- a/include/hw/virtio/vhost.h
> >+++ b/include/hw/virtio/vhost.h
> >@@ -100,6 +100,10 @@ int vhost_dev_start(struct vhost_dev *hdev,
> >VirtIODevice *vdev);
> > void vhost_dev_stop(struct vhost_dev *hdev, VirtIODevice *vdev);
> > int vhost_dev_enable_notifiers(struct vhost_dev *hdev, VirtIODevice *vdev);
> > void vhost_dev_disable_notifiers(struct vhost_dev *hdev, VirtIODevice
> > *vdev);
> >+int vhost_dev_assign_guest_notifiers(struct vhost_dev *hdev,
> >+ VirtIODevice *vdev, int nvqs);
> >+int vhost_dev_drop_guest_notifiers(struct vhost_dev *hdev,
> >+ VirtIODevice *vdev, int nvqs);
> > /* Test and clear masked event pending status.
> > * Should be called after unmask to avoid losing events.
> >diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
> >index b69d517..d9a3d72 100644
> >--- a/include/hw/virtio/virtio.h
> >+++ b/include/hw/virtio/virtio.h
> >@@ -323,6 +323,7 @@ void
> >virtio_queue_aio_set_host_notifier_handler(VirtQueue *vq, AioContext *ctx,
> > VirtIOHandleAIOOutput
> > handle_output);
> > VirtQueue *virtio_vector_first_queue(VirtIODevice *vdev, uint16_t vector);
> > VirtQueue *virtio_vector_next_queue(VirtQueue *vq);
> >+bool virtio_device_guest_notifiers_initialized(VirtIODevice *vdev);
> > static inline void virtio_add_feature(uint64_t *features, unsigned int
> > fbit)
> > {
>