[Qemu-devel] [RESEND Patch v1 09/37] vhost-pci-slave/msg: VHOST_USER_GET_PROTOCOL_FEATURES

[Wei Wang]

Add a new protocol feature, VHOST_USER_PROTOCOL_F_VHOST_PCI. This
feature indicates the support of the vhost-pci extension for inter-vm
communiaction.

Signed-off-by: Wei Wang <address@hidden>
---
 hw/virtio/vhost-pci-slave.c    | 16 ++++++++++++++++
 include/hw/virtio/vhost-user.h |  6 ++++++
 2 files changed, 22 insertions(+)

diff --git a/hw/virtio/vhost-pci-slave.c b/hw/virtio/vhost-pci-slave.c
index 68ab4ec..05255d1 100644
--- a/hw/virtio/vhost-pci-slave.c
+++ b/hw/virtio/vhost-pci-slave.c
@@ -62,6 +62,16 @@ static void vp_slave_event(void *opaque, int event)
     }
 }
 
+static int vp_slave_get_protocol_features(CharBackend *chr_be,
+                                          VhostUserMsg *msg)
+{
+    msg->payload.u64 = VHOST_USER_PROTOCOL_FEATURES;
+    msg->size = sizeof(msg->payload.u64);
+    msg->flags |= VHOST_USER_REPLY_MASK;
+
+    return vp_slave_write(chr_be, msg);
+}
+
 static int vp_slave_can_read(void *opaque)
 {
     return VHOST_USER_HDR_SIZE;
@@ -105,6 +115,12 @@ static void vp_slave_read(void *opaque, const uint8_t 
*buf, int size)
     case VHOST_USER_SET_FEATURES:
         vp_slave_set_features(&msg);
         break;
+    case VHOST_USER_GET_PROTOCOL_FEATURES:
+        ret = vp_slave_get_protocol_features(chr_be, &msg);
+        if (ret < 0) {
+            goto err_handling;
+        }
+        break;
     default:
         error_report("vhost-pci-slave does not support msg request = %d",
                      msg.request);
diff --git a/include/hw/virtio/vhost-user.h b/include/hw/virtio/vhost-user.h
index 8d43ffc..ad5eac9 100644
--- a/include/hw/virtio/vhost-user.h
+++ b/include/hw/virtio/vhost-user.h
@@ -11,12 +11,18 @@ enum VhostUserProtocolFeature {
     VHOST_USER_PROTOCOL_F_LOG_SHMFD = 1,
     VHOST_USER_PROTOCOL_F_RARP = 2,
     VHOST_USER_PROTOCOL_F_REPLY_ACK = 3,
+    VHOST_USER_PROTOCOL_F_VHOST_PCI = 4,
 
     VHOST_USER_PROTOCOL_F_MAX
 };
 
 #define VHOST_USER_PROTOCOL_FEATURE_MASK ((1 << VHOST_USER_PROTOCOL_F_MAX) - 1)
 
+#define VHOST_USER_PROTOCOL_FEATURES ((1ULL << VHOST_USER_PROTOCOL_F_MQ) | \
+                               (1ULL << VHOST_USER_PROTOCOL_F_LOG_SHMFD) | \
+                                    (1ULL << VHOST_USER_PROTOCOL_F_RARP) | \
+                              (1ULL << VHOST_USER_PROTOCOL_F_VHOST_PCI))
+
 typedef enum VhostUserRequest {
     VHOST_USER_NONE = 0,
     VHOST_USER_GET_FEATURES = 1,
-- 
2.7.4