vhost: introduce API to fetch negotiated features

Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

diff --git a/lib/librte_vhost/rte_vhost_version.map b/lib/librte_vhost/rte_vhost_version.map
index 664a5f3..cec1e9e 100644 (file)
--- a/lib/librte_vhost/rte_vhost_version.map
+++ b/lib/librte_vhost/rte_vhost_version.map
@@ -37,5 +37,6 @@ DPDK_17.05 {
        rte_vhost_driver_set_features;
        rte_vhost_get_mem_table;
        rte_vhost_get_mtu;
+       rte_vhost_get_negotiated_features;
 
 } DPDK_16.07;

diff --git a/lib/librte_vhost/rte_virtio_net.h b/lib/librte_vhost/rte_virtio_net.h
index 7883266..e365597 100644 (file)
--- a/lib/librte_vhost/rte_virtio_net.h
+++ b/lib/librte_vhost/rte_virtio_net.h
@@ -158,6 +158,18 @@ int rte_vhost_driver_disable_features(const char *path, uint64_t features);
  */
 int rte_vhost_driver_get_features(const char *path, uint64_t *features);
 
+/**
+ * Get the feature bits after negotiation
+ *
+ * @param vid
+ *  Vhost device ID
+ * @param features
+ *  A pointer to store the queried feature bits
+ * @return
+ *  0 on success, -1 on failure
+ */
+int rte_vhost_get_negotiated_features(int vid, uint64_t *features);
+
 /* Register callbacks. */
 int rte_vhost_driver_callback_register(const char *path,
        struct virtio_net_device_ops const * const ops);

diff --git a/lib/librte_vhost/vhost.c b/lib/librte_vhost/vhost.c
index 2b41652..90b0f67 100644 (file)
--- a/lib/librte_vhost/vhost.c
+++ b/lib/librte_vhost/vhost.c
@@ -359,6 +359,19 @@ rte_vhost_get_ifname(int vid, char *buf, size_t len)
        return 0;
 }
 
+int
+rte_vhost_get_negotiated_features(int vid, uint64_t *features)
+{
+       struct virtio_net *dev;
+
+       dev = get_device(vid);
+       if (!dev)
+               return -1;
+
+       *features = dev->features;
+       return 0;
+}
+
 int
 rte_vhost_get_mem_table(int vid, struct rte_vhost_memory **mem)
 {