[Qemu-devel] [PATCH] vhost-vsock: support parse mergeable feature

[jiangyiwen <jiangyiwen@huawei.com>]

Currently vhost-vsock doesn't have any feature bits, so it
don't support parse mergeable rx buffer feature. And the
feature is support in another series of patches named
"VSOCK: support mergeable rx buffer in vhost-vsock".

So we neet to support parse mergeable feature in vhost-vsock
if above patches are merged.

Signed-off-by: Yiwen Jiang <jiangyiwen@huawei.com>
---
 hw/virtio/vhost-vsock.c                       | 9 +++++++--
 include/standard-headers/linux/virtio_vsock.h | 3 +++
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/hw/virtio/vhost-vsock.c b/hw/virtio/vhost-vsock.c
index aa5af92..5023c05 100644
--- a/hw/virtio/vhost-vsock.c
+++ b/hw/virtio/vhost-vsock.c
@@ -178,8 +178,13 @@ static uint64_t vhost_vsock_get_features(VirtIODevice *vdev,
                                          uint64_t requested_features,
                                          Error **errp)
 {
-    /* No feature bits used yet */
-    return requested_features;
+    VHostVSock *vsock = VHOST_VSOCK(vdev);
+    uint64_t features;
+
+    virtio_add_feature(&requested_features, VIRTIO_VSOCK_F_MRG_RXBUF);
+    features = requested_features & vsock->vhost_dev.features;
+
+    return features;
 }

 static void vhost_vsock_handle_output(VirtIODevice *vdev, VirtQueue *vq)
diff --git a/include/standard-headers/linux/virtio_vsock.h b/include/standard-headers/linux/virtio_vsock.h
index be44321..4c583ec 100644
--- a/include/standard-headers/linux/virtio_vsock.h
+++ b/include/standard-headers/linux/virtio_vsock.h
@@ -38,6 +38,9 @@
 #include "standard-headers/linux/virtio_ids.h"
 #include "standard-headers/linux/virtio_config.h"

+/* Virtio-vsock feature */
+#define VIRTIO_VSOCK_F_MRG_RXBUF 0 /* Host can merge receive buffers. */
+
 struct virtio_vsock_config {
 	uint64_t guest_cid;
 } QEMU_PACKED;
-- 
1.8.3.1