From 8899d60142e790debe1604a89d0028ba1740d8e9 Mon Sep 17 00:00:00 2001
From: Johannes Berg <johannes.berg@intel.com>
Date: Thu, 23 Jan 2020 09:17:03 +0100
Subject: [PATCH] libvhost-user: implement VHOST_USER_PROTOCOL_F_REPLY_ACK
This is really simple, since we know whether a response is
already requested or not, so we can just send a (successful)
response when there isn't one already.
Given that, it's not all _that_ useful but the master can at
least be sure the message was processed, and we can exercise
more code paths using the example code.
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Message-Id: <20200123081708.7817-2-johannes@sipsolutions.net>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
contrib/libvhost-user/libvhost-user.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c
index b89bf18501..533d55d82a 100644
--- a/contrib/libvhost-user/libvhost-user.c
+++ b/contrib/libvhost-user/libvhost-user.c
@@ -1199,7 +1199,8 @@ vu_get_protocol_features_exec(VuDev *dev, VhostUserMsg *vmsg)
1ULL << VHOST_USER_PROTOCOL_F_LOG_SHMFD |
1ULL << VHOST_USER_PROTOCOL_F_SLAVE_REQ |
1ULL << VHOST_USER_PROTOCOL_F_HOST_NOTIFIER |
- 1ULL << VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD;
+ 1ULL << VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD |
+ 1ULL << VHOST_USER_PROTOCOL_F_REPLY_ACK;
if (have_userfault()) {
features |= 1ULL << VHOST_USER_PROTOCOL_F_PAGEFAULT;
@@ -1581,13 +1582,20 @@ vu_dispatch(VuDev *dev)
{
VhostUserMsg vmsg = { 0, };
int reply_requested;
- bool success = false;
+ bool need_reply, success = false;
if (!vu_message_read(dev, dev->sock, &vmsg)) {
goto end;
}
+ need_reply = vmsg.flags & VHOST_USER_NEED_REPLY_MASK;
+
reply_requested = vu_process_message(dev, &vmsg);
+ if (!reply_requested && need_reply) {
+ vmsg_set_reply_u64(&vmsg, 0);
+ reply_requested = 1;
+ }
+
if (!reply_requested) {
success = true;
goto end;
--
2.30.2