在 2022/11/16 23:05, Eugenio Pérez 写道:
Isolate control virtqueue in its own group, allowing to intercept control
commands but letting dataplane run totally passthrough to the guest.
Signed-off-by: Eugenio Pérez <eperezma@xxxxxxxxxx>
---
v7:
* Never ask for number of address spaces, just react if isolation is not
possible.
* Return ASID ioctl errors instead of masking them as if the device has
no asid.
* Simplify net_init_vhost_vdpa logic
* Add "if possible" suffix
v6:
* Disable control SVQ if the device does not support it because of
features.
v5:
* Fixing the not adding cvq buffers when x-svq=on is specified.
* Move vring state in vhost_vdpa_get_vring_group instead of using a
parameter.
* Rename VHOST_VDPA_NET_CVQ_PASSTHROUGH to VHOST_VDPA_NET_DATA_ASID
v4:
* Squash vhost_vdpa_cvq_group_is_independent.
* Rebased on last CVQ start series, that allocated CVQ cmd bufs at load
* Do not check for cvq index on vhost_vdpa_net_prepare, we only have one
that callback registered in that NetClientInfo.
v3:
* Make asid related queries print a warning instead of returning an
error and stop the start of qemu.
---
hw/virtio/vhost-vdpa.c | 3 +-
net/vhost-vdpa.c | 117 +++++++++++++++++++++++++++++++++++++++--
2 files changed, 114 insertions(+), 6 deletions(-)
diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index 852baf8b2c..a29a18a6a9 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -653,7 +653,8 @@ static int vhost_vdpa_set_backend_cap(struct vhost_dev *dev)
{
uint64_t features;
uint64_t f = 0x1ULL << VHOST_BACKEND_F_IOTLB_MSG_V2 |
- 0x1ULL << VHOST_BACKEND_F_IOTLB_BATCH;
+ 0x1ULL << VHOST_BACKEND_F_IOTLB_BATCH |
+ 0x1ULL << VHOST_BACKEND_F_IOTLB_ASID;
int r;
if (vhost_vdpa_call(dev, VHOST_GET_BACKEND_FEATURES, &features)) {
diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index a9c864741a..dc13a49311 100644
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -101,6 +101,8 @@ static const uint64_t vdpa_svq_device_features =
BIT_ULL(VIRTIO_NET_F_RSC_EXT) |
BIT_ULL(VIRTIO_NET_F_STANDBY);
+#define VHOST_VDPA_NET_CVQ_ASID 1
+
VHostNetState *vhost_vdpa_get_vhost_net(NetClientState *nc)
{
VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
@@ -242,6 +244,40 @@ static NetClientInfo net_vhost_vdpa_info = {
.check_peer_type = vhost_vdpa_check_peer_type,
};
+static int64_t vhost_vdpa_get_vring_group(int device_fd, unsigned vq_index)
+{
+ struct vhost_vring_state state = {
+ .index = vq_index,
+ };
+ int r = ioctl(device_fd, VHOST_VDPA_GET_VRING_GROUP, &state);
+
+ if (unlikely(r < 0)) {
+ error_report("Cannot get VQ %u group: %s", vq_index,
+ g_strerror(errno));
+ return r;
+ }
+
+ return state.num;
+}
+
+static int vhost_vdpa_set_address_space_id(struct vhost_vdpa *v,
+ unsigned vq_group,
+ unsigned asid_num)
+{
+ struct vhost_vring_state asid = {
+ .index = vq_group,
+ .num = asid_num,
+ };
+ int r;
+
+ r = ioctl(v->device_fd, VHOST_VDPA_SET_GROUP_ASID, &asid);
+ if (unlikely(r < 0)) {
+ error_report("Can't set vq group %u asid %u, errno=%d (%s)",
+ asid.index, asid.num, errno, g_strerror(errno));
+ }
+ return r;
+}
+
static void vhost_vdpa_cvq_unmap_buf(struct vhost_vdpa *v, void *addr)
{
VhostIOVATree *tree = v->iova_tree;
@@ -316,11 +352,69 @@ dma_map_err:
static int vhost_vdpa_net_cvq_start(NetClientState *nc)
{
VhostVDPAState *s;
- int r;
+ struct vhost_vdpa *v;
+ uint64_t backend_features;
+ int64_t cvq_group;
+ int cvq_index, r;
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
s = DO_UPCAST(VhostVDPAState, nc, nc);
+ v = &s->vhost_vdpa;
+
+ v->shadow_data = s->always_svq;
+ v->shadow_vqs_enabled = s->always_svq;
+ s->vhost_vdpa.address_space_id = VHOST_VDPA_GUEST_PA_ASID;
+
+ if (s->always_svq) {
+ goto out;
+ }
+
+ /* Backend features are not available in v->dev yet. */
+ r = ioctl(v->device_fd, VHOST_GET_BACKEND_FEATURES, &backend_features);
+ if (unlikely(r < 0)) {
+ error_report("Cannot get vdpa backend_features: %s(%d)",
+ g_strerror(errno), errno);
+ return -1;
+ }
+ if (!(backend_features & VHOST_BACKEND_F_IOTLB_ASID) ||
+ !vhost_vdpa_net_valid_svq_features(v->dev->features, NULL)) {
I think there should be some logic to block migration in this case?
+ return 0;
+ }
+
+ /**
+ * Check if all the virtqueues of the virtio device are in a different vq
+ * than the last vq. VQ group of last group passed in cvq_group.
+ */
+ cvq_index = v->dev->vq_index_end - 1;
+ cvq_group = vhost_vdpa_get_vring_group(v->device_fd, cvq_index);
+ if (unlikely(cvq_group < 0)) {
+ return cvq_group;x
+ }
+ for (int i = 0; i < cvq_index; ++i) {
+ int64_t group = vhost_vdpa_get_vring_group(v->device_fd, i);
+
+ if (unlikely(group < 0)) {
+ return group;
+ }
+
+ if (unlikely(group == cvq_group)) {
+ warn_report(
+ "CVQ %"PRId64" group is the same as VQ %d one (%"PRId64")",
+ cvq_group, i, group);
+ return 0;
Ditto.
+ }
+ }
+
+ r = vhost_vdpa_set_address_space_id(v, cvq_group, VHOST_VDPA_NET_CVQ_ASID);
+ if (unlikely(r < 0)) {
+ return r;
+ } else {
+ v->shadow_vqs_enabled = true;
+ s->vhost_vdpa.address_space_id = VHOST_VDPA_NET_CVQ_ASID;
+ }
+
+out:
if (!s->vhost_vdpa.shadow_vqs_enabled) {
return 0;
}
@@ -652,6 +746,7 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
g_autoptr(VhostIOVATree) iova_tree = NULL;
NetClientState *nc;
int queue_pairs, r, i = 0, has_cvq = 0;
+ bool svq_cvq;
assert(netdev->type == NET_CLIENT_DRIVER_VHOST_VDPA);
opts = &netdev->u.vhost_vdpa;
@@ -693,12 +788,24 @@ int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
return queue_pairs;
}
- if (opts->x_svq) {
- struct vhost_vdpa_iova_range iova_range;
+ svq_cvq = opts->x_svq || has_cvq;
+ if (svq_cvq) {
+ Error *warn = NULL;
- if (!vhost_vdpa_net_valid_svq_features(features, errp)) {
- goto err_svq;
+ svq_cvq = vhost_vdpa_net_valid_svq_features(features,
+ opts->x_svq ? errp : &warn);
+ if (!svq_cvq) {
+ if (opts->x_svq) {
+ goto err_svq;
+ } else {
+ warn_reportf_err(warn, "Cannot shadow CVQ: ");
This seems suspicious, we reach here we we can't just use svq for cvq.
+ }
}
The above logic is not easy to follow. I guess the root cause is the
variable name. It looks to me svq_cvq is better to be renamed as "svq"?
Thanks
+ }
+
+ if (svq_cvq) {
+ /* Allocate a common iova tree if there is a possibility of SVQ */
+ struct vhost_vdpa_iova_range iova_range;
vhost_vdpa_get_iova_range(vdpa_device_fd, &iova_range);
iova_tree = vhost_iova_tree_new(iova_range.first, iova_range.last);
