This field is mostly unused and sometimes confusing. We even have
a TODO-like comment to drop it, the comment is removed in this commit.
The field is used to held VHOST_USER_F_PROTOCOL_FEATURES for vhost-user
and/or VHOST_NET_F_VIRTIO_NET_HDR for vhost-net (which may be
vhost-user-net). But we can simply recalculate these two flags in place
from hdev->features, and from net-client for VHOST_NET_F_VIRTIO_NET_HDR.
Note: removing field from x-query-virtio-status result is incompatible
change. We can do it because the command is unstable.
Cc: devel@lists.libvirt.org
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Acked-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniil Tatianin <d-tatianin@yandex-team.ru>
Acked-by: Raphael Norwitz <raphael.s.norwitz@gmail.com>
---
hw/block/vhost-user-blk.c | 1 -
hw/net/vhost_net.c | 26 ++++++++++++++------------
hw/scsi/vhost-scsi.c | 1 -
hw/scsi/vhost-user-scsi.c | 1 -
hw/virtio/vdpa-dev.c | 1 -
hw/virtio/vhost-user.c | 17 ++++++++---------
hw/virtio/virtio-hmp-cmds.c | 2 --
hw/virtio/virtio-qmp.c | 4 ----
include/hw/virtio/vhost.h | 7 -------
qapi/virtio.json | 3 ---
10 files changed, 22 insertions(+), 41 deletions(-)
diff --git a/hw/block/vhost-user-blk.c b/hw/block/vhost-user-blk.c
index c0cc5f6942..de7a810c93 100644
--- a/hw/block/vhost-user-blk.c
+++ b/hw/block/vhost-user-blk.c
@@ -348,7 +348,6 @@ static int vhost_user_blk_connect(DeviceState *dev, Error **errp)
s->dev.nvqs = s->num_queues;
s->dev.vqs = s->vhost_vqs;
s->dev.vq_index = 0;
- s->dev.backend_features = 0;
vhost_dev_set_config_notifier(&s->dev, &blk_ops);
diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
index 25e9f1fd24..fda90e231e 100644
--- a/hw/net/vhost_net.c
+++ b/hw/net/vhost_net.c
@@ -52,8 +52,14 @@ int vhost_net_set_config(struct vhost_net *net, const uint8_t *data,
void vhost_net_ack_features_ex(struct vhost_net *net, const uint64_t *features)
{
- virtio_features_copy(net->dev.acked_features_ex,
- net->dev.backend_features_ex);
+ virtio_features_clear(net->dev.acked_features_ex);
+ if (net->backend == -1) {
+ net->dev.acked_features =
+ net->dev.features & (1ULL << VHOST_USER_F_PROTOCOL_FEATURES);
+ } else if (!qemu_has_vnet_hdr(net->nc)) {
+ net->dev.acked_features = 1ULL << VHOST_NET_F_VIRTIO_NET_HDR;
+ }
+
vhost_ack_features_ex(&net->dev, net->feature_bits, features);
}
@@ -258,12 +264,9 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
if (r < 0) {
goto fail;
}
- net->dev.backend_features = qemu_has_vnet_hdr(options->net_backend)
- ? 0 : (1ULL << VHOST_NET_F_VIRTIO_NET_HDR);
net->backend = r;
net->dev.protocol_features = 0;
} else {
- virtio_features_clear(net->dev.backend_features_ex);
net->dev.protocol_features = 0;
net->backend = -1;
@@ -284,13 +287,12 @@ struct vhost_net *vhost_net_init(VhostNetOptions *options)
net->dev.features &= ~(1ULL << VIRTIO_NET_F_MRG_RXBUF);
}
- if (virtio_features_andnot(missing_features,
- net->dev.backend_features_ex,
- net->dev.features_ex)) {
- fprintf(stderr, "vhost lacks feature mask 0x" VIRTIO_FEATURES_FMT
- " for backend\n", VIRTIO_FEATURES_PR(missing_features));
- goto fail;
- }
+ if (!qemu_has_vnet_hdr(options->net_backend) &&
+ (~net->dev.features & (1ULL << VHOST_NET_F_VIRTIO_NET_HDR))) {
+ fprintf(stderr, "vhost lacks feature mask 0x%llx for backend\n",
+ ~net->dev.features & (1ULL << VHOST_NET_F_VIRTIO_NET_HDR));
+ goto fail;
+ }
}
/* Set sane init value. Override when guest acks. */
diff --git a/hw/scsi/vhost-scsi.c b/hw/scsi/vhost-scsi.c
index cdf405b0f8..d694a25fe2 100644
--- a/hw/scsi/vhost-scsi.c
+++ b/hw/scsi/vhost-scsi.c
@@ -276,7 +276,6 @@ static void vhost_scsi_realize(DeviceState *dev, Error **errp)
vqs = g_new0(struct vhost_virtqueue, vsc->dev.nvqs);
vsc->dev.vqs = vqs;
vsc->dev.vq_index = 0;
- vsc->dev.backend_features = 0;
ret = vhost_dev_init(&vsc->dev, (void *)(uintptr_t)vhostfd,
VHOST_BACKEND_TYPE_KERNEL, 0, errp);
diff --git a/hw/scsi/vhost-user-scsi.c b/hw/scsi/vhost-user-scsi.c
index 25f2d894e7..0c80a271d8 100644
--- a/hw/scsi/vhost-user-scsi.c
+++ b/hw/scsi/vhost-user-scsi.c
@@ -159,7 +159,6 @@ static int vhost_user_scsi_connect(DeviceState *dev, Error **errp)
vsc->dev.nvqs = VIRTIO_SCSI_VQ_NUM_FIXED + vs->conf.num_queues;
vsc->dev.vqs = s->vhost_vqs;
vsc->dev.vq_index = 0;
- vsc->dev.backend_features = 0;
ret = vhost_dev_init(&vsc->dev, &s->vhost_user, VHOST_BACKEND_TYPE_USER, 0,
errp);
diff --git a/hw/virtio/vdpa-dev.c b/hw/virtio/vdpa-dev.c
index 4a7b970976..efd9f68420 100644
--- a/hw/virtio/vdpa-dev.c
+++ b/hw/virtio/vdpa-dev.c
@@ -104,7 +104,6 @@ static void vhost_vdpa_device_realize(DeviceState *dev, Error **errp)
v->dev.vqs = vqs;
v->dev.vq_index = 0;
v->dev.vq_index_end = v->dev.nvqs;
- v->dev.backend_features = 0;
v->started = false;
ret = vhost_vdpa_get_iova_range(v->vhostfd, &iova_range);
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index f367ce06ce..b80174f489 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -1448,14 +1448,15 @@ static int vhost_user_set_features(struct vhost_dev *dev,
int ret;
/*
- * We need to include any extra backend only feature bits that
- * might be needed by our device. Currently this includes the
- * VHOST_USER_F_PROTOCOL_FEATURES bit for enabling protocol
- * features.
+ * Don't lose VHOST_USER_F_PROTOCOL_FEATURES, which is vhost-user
+ * specific.
*/
- ret = vhost_user_set_u64(dev, VHOST_USER_SET_FEATURES,
- features | dev->backend_features,
- log_enabled);
+ if (virtio_has_feature(dev->features, VHOST_USER_F_PROTOCOL_FEATURES)) {
+ features |= 1ULL << VHOST_USER_F_PROTOCOL_FEATURES;
+ }
+
+ ret = vhost_user_set_u64(dev, VHOST_USER_SET_FEATURES, features,
+ log_enabled);
if (virtio_has_feature(dev->protocol_features,
VHOST_USER_PROTOCOL_F_STATUS)) {
@@ -2189,8 +2190,6 @@ static int vhost_user_backend_init(struct vhost_dev *dev, void *opaque,
(dev->config_ops && dev->config_ops->vhost_dev_config_notifier);
uint64_t protocol_features;
- dev->backend_features |= 1ULL << VHOST_USER_F_PROTOCOL_FEATURES;
-
err = vhost_user_get_u64(dev, VHOST_USER_GET_PROTOCOL_FEATURES,
&protocol_features);
if (err < 0) {
diff --git a/hw/virtio/virtio-hmp-cmds.c b/hw/virtio/virtio-hmp-cmds.c
index 1daae482d3..4bf9a3109d 100644
--- a/hw/virtio/virtio-hmp-cmds.c
+++ b/hw/virtio/virtio-hmp-cmds.c
@@ -176,8 +176,6 @@ void hmp_virtio_status(Monitor *mon, const QDict *qdict)
hmp_virtio_dump_features(mon, s->vhost_dev->features);
monitor_printf(mon, " Acked features:\n");
hmp_virtio_dump_features(mon, s->vhost_dev->acked_features);
- monitor_printf(mon, " Backend features:\n");
- hmp_virtio_dump_features(mon, s->vhost_dev->backend_features);
monitor_printf(mon, " Protocol features:\n");
hmp_virtio_dump_protocols(mon, s->vhost_dev->protocol_features);
}
diff --git a/hw/virtio/virtio-qmp.c b/hw/virtio/virtio-qmp.c
index b338344c6c..dd1a38e792 100644
--- a/hw/virtio/virtio-qmp.c
+++ b/hw/virtio/virtio-qmp.c
@@ -780,8 +780,6 @@ VirtioStatus *qmp_x_query_virtio_status(const char *path, Error **errp)
vdev->guest_features_ex);
status->host_features = qmp_decode_features(vdev->device_id,
vdev->host_features_ex);
- status->backend_features = qmp_decode_features(vdev->device_id,
- vdev->backend_features_ex);
switch (vdev->device_endian) {
case VIRTIO_DEVICE_ENDIAN_LITTLE:
@@ -822,8 +820,6 @@ VirtioStatus *qmp_x_query_virtio_status(const char *path, Error **errp)
qmp_decode_features(vdev->device_id, hdev->features_ex);
status->vhost_dev->acked_features =
qmp_decode_features(vdev->device_id, hdev->acked_features_ex);
- status->vhost_dev->backend_features =
- qmp_decode_features(vdev->device_id, hdev->backend_features_ex);
status->vhost_dev->protocol_features =
qmp_decode_protocols(hdev->protocol_features);
diff --git a/include/hw/virtio/vhost.h b/include/hw/virtio/vhost.h
index 1ee639dd7e..3e69e47833 100644
--- a/include/hw/virtio/vhost.h
+++ b/include/hw/virtio/vhost.h
@@ -100,16 +100,9 @@ struct vhost_dev {
*
* @features: available features provided by the backend
* @acked_features: final negotiated features with front-end driver
- *
- * @backend_features: this is used in a couple of places to either
- * store VHOST_USER_F_PROTOCOL_FEATURES to apply to
- * VHOST_USER_SET_FEATURES or VHOST_NET_F_VIRTIO_NET_HDR. Its
- * future use should be discouraged and the variable retired as
- * its easy to confuse with the VirtIO backend_features.
*/
VIRTIO_DECLARE_FEATURES(features);
VIRTIO_DECLARE_FEATURES(acked_features);
- VIRTIO_DECLARE_FEATURES(backend_features);
/**
* @protocol_features: is the vhost-user only feature set by
diff --git a/qapi/virtio.json b/qapi/virtio.json
index 05295ab665..b995a5bb6d 100644
--- a/qapi/virtio.json
+++ b/qapi/virtio.json
@@ -85,8 +85,6 @@
#
# @acked-features: vhost_dev acked_features
#
-# @backend-features: vhost_dev backend_features
-#
# @protocol-features: vhost_dev protocol_features
#
# @max-queues: vhost_dev max_queues
@@ -106,7 +104,6 @@
'vq-index': 'int',
'features': 'VirtioDeviceFeatures',
'acked-features': 'VirtioDeviceFeatures',
- 'backend-features': 'VirtioDeviceFeatures',
'protocol-features': 'VhostDeviceProtocols',
'max-queues': 'uint64',
'backend-cap': 'uint64',
--
2.48.1