[PATCH 2/5] vdpa: Add vhost_vdpa_net_load_mq

[Eugenio Pérez]

Same way as with the MAC, restore the expected number of queues at
device's start.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
 net/vhost-vdpa.c | 33 +++++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index 1e0dbfcced..96fd3bc835 100644
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -391,6 +391,35 @@ static int vhost_vdpa_net_load_mac(VhostVDPAState *s,
     return 0;
 }
 
+static int vhost_vdpa_net_load_mq(VhostVDPAState *s,
+                                  const VirtIONet *n)
+{
+    uint64_t features = n->parent_obj.guest_features;
+    ssize_t dev_written;
+    void *cursor = s->cvq_cmd_out_buffer;
+    if (!(features & BIT_ULL(VIRTIO_NET_F_MQ))) {
+        return 0;
+    }
+
+    *(struct virtio_net_ctrl_hdr *)cursor = (struct virtio_net_ctrl_hdr) {
+        .class = VIRTIO_NET_CTRL_MQ,
+        .cmd = VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET,
+    };
+    cursor += sizeof(struct virtio_net_ctrl_hdr);
+    *(struct virtio_net_ctrl_mq *)cursor = (struct virtio_net_ctrl_mq) {
+        .virtqueue_pairs = cpu_to_le16(n->curr_queue_pairs),
+    };
+    cursor += sizeof(struct virtio_net_ctrl_mq);
+
+    dev_written = vhost_vdpa_net_cvq_add(s, cursor - s->cvq_cmd_out_buffer,
+                                             sizeof(virtio_net_ctrl_ack));
+    if (unlikely(dev_written < 0)) {
+        return dev_written;
+    }
+
+    return *((virtio_net_ctrl_ack *)s->cvq_cmd_in_buffer) != VIRTIO_NET_OK;
+}
+
 static int vhost_vdpa_net_load(NetClientState *nc)
 {
     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
@@ -409,6 +438,10 @@ static int vhost_vdpa_net_load(NetClientState *nc)
     if (unlikely(r < 0)) {
         return r;
     }
+    r = vhost_vdpa_net_load_mq(s, n);
+    if (unlikely(r)) {
+        return r;
+    }
 
     return 0;
 }
-- 
2.31.1