Re: [RFC v2 9/9] vhost: introduce vhost_set_vring_ready method

[Jason Wang]

On 2020/5/9 上午12:32, Cindy Lu wrote:

From: Jason Wang <jasow...@redhat.com>

Vhost-vdpa introduces VHOST_VDPA_SET_VRING_ENABLE which complies the
semantic of queue_enable defined in virtio spec. This method can be
used for preventing device from executing request for a specific
virtqueue. This patch introduces the vhost_ops for this.

Note that, we've already had vhost_set_vring_enable which has different
semantic which allows to enable or disable a specific virtqueue for
some kinds of vhost backends. E.g vhost-user use this to changes the
number of active queue pairs.

Signed-off-by: Jason Wang <jasow...@redhat.com>

Similarly, please place this patch before vhost-vdpa patches.

Thanks

---
  hw/net/vhost_net-stub.c |  4 ++++
  hw/net/vhost_net.c      | 11 ++++++++++-
  include/net/vhost_net.h |  1 +
  3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/hw/net/vhost_net-stub.c b/hw/net/vhost_net-stub.c
index aac0e98228..43e93e1a9a 100644
--- a/hw/net/vhost_net-stub.c
+++ b/hw/net/vhost_net-stub.c
@@ -86,6 +86,10 @@ int vhost_set_vring_enable(NetClientState *nc, int enable)
      return 0;
  }

+int vhost_set_vring_ready(NetClientState *nc)

+{
+    return 0;
+}
  int vhost_net_set_mtu(struct vhost_net *net, uint16_t mtu)
  {
      return 0;
diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
index eff9ec9177..6911282a0a 100644
--- a/hw/net/vhost_net.c
+++ b/hw/net/vhost_net.c
@@ -375,7 +375,7 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
              goto err_start;
          }

- if (ncs[i].peer->vring_enable) {

+        if (peer->vring_enable) {
              /* restore vring enable state */
              r = vhost_set_vring_enable(peer, peer->vring_enable);

@@ -496,6 +496,15 @@ int vhost_set_vring_enable(NetClientState *nc, int enable)

      return 0;
  }

+int vhost_set_vring_ready(NetClientState *nc)

+{
+    VHostNetState *net = get_vhost_net(nc);
+    const VhostOps *vhost_ops = net->dev.vhost_ops;
+    if (vhost_ops && vhost_ops->vhost_set_vring_ready) {
+        return vhost_ops->vhost_set_vring_ready(&net->dev);
+    }
+    return 0;
+}
  int vhost_net_set_mtu(struct vhost_net *net, uint16_t mtu)
  {
      const VhostOps *vhost_ops = net->dev.vhost_ops;
diff --git a/include/net/vhost_net.h b/include/net/vhost_net.h
index b47844bf29..247432a3b2 100644
--- a/include/net/vhost_net.h
+++ b/include/net/vhost_net.h
@@ -35,6 +35,7 @@ int vhost_net_notify_migration_done(VHostNetState *net, char* 
mac_addr);
  VHostNetState *get_vhost_net(NetClientState *nc);

int vhost_set_vring_enable(NetClientState * nc, int enable);

+int vhost_set_vring_ready(NetClientState *nc);

uint64_t vhost_net_get_acked_features(VHostNetState *net);