[PATCH v2 1/2] vhost: support VIRTIO_F_RING_RESET for vhost-user

[Kangjie Xu <kangjie.xu@linux.alibaba.com>]

Add VIRTIO_F_RING_RESET, which indicates that the driver can reset a
queue individually.

The feature is added to virtio-spec 1.2. The relevant information is
in https://github.com/oasis-tcs/virtio-spec/issues/124

Signed-off-by: Kangjie Xu <kangjie.xu@linux.alibaba.com>
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
---
 lib/vhost/vhost.h | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lib/vhost/vhost.h b/lib/vhost/vhost.h
index 40fac3b7c6..76461a3406 100644
--- a/lib/vhost/vhost.h
+++ b/lib/vhost/vhost.h
@@ -376,6 +376,11 @@ struct vhost_msg {
  #define VIRTIO_F_VERSION_1 32
 #endif
 
+/* This feature indicates that the driver can reset a queue individually. */
+#ifndef VIRTIO_F_RING_RESET
+#define VIRTIO_F_RING_RESET 40
+#endif
+
 /* Declare packed ring related bits for older kernels */
 #ifndef VIRTIO_F_RING_PACKED
 
@@ -438,7 +443,8 @@ struct vring_packed_desc_event {
 				(1ULL << VIRTIO_NET_F_MTU)  | \
 				(1ULL << VIRTIO_F_IN_ORDER) | \
 				(1ULL << VIRTIO_F_IOMMU_PLATFORM) | \
-				(1ULL << VIRTIO_F_RING_PACKED))
+				(1ULL << VIRTIO_F_RING_PACKED)	| \
+				(1ULL << VIRTIO_F_RING_RESET))
 
 
 struct guest_page {
-- 
2.32.0