From 3a223111d71307eb4fdc18f5ee46ce3d6cb57660 Mon Sep 17 00:00:00 2001
From: Jinhua Cao <caojinhua1@huawei.com>
Date: Fri, 11 Feb 2022 18:05:47 +0800
Subject: [PATCH] vhost-user: Add support reconnect vhost-user socket

Add support reconnect vhost-user socket, the reconnect time
is set to be 3 seconds.

Signed-off-by: Jinhua Cao <caojinhua1@huawei.com>
---
 chardev/char-socket.c  | 19 ++++++++++++++++++-
 hw/net/vhost_net.c     |  4 +++-
 hw/virtio/vhost-user.c |  6 ++++++
 include/chardev/char.h | 16 ++++++++++++++++
 net/vhost-user.c       |  3 +++
 5 files changed, 46 insertions(+), 2 deletions(-)

diff --git a/chardev/char-socket.c b/chardev/char-socket.c
index 836cfa0bc2..b1e9f43ec6 100644
--- a/chardev/char-socket.c
+++ b/chardev/char-socket.c
@@ -393,6 +393,22 @@ static GSource *tcp_chr_add_watch(Chardev *chr, GIOCondition cond)
     return qio_channel_create_watch(s->ioc, cond);
 }
 
+static void tcp_chr_set_reconnect_time(Chardev *chr,
+                                       int64_t reconnect_time)
+{
+    SocketChardev *s = SOCKET_CHARDEV(chr);
+    s->reconnect_time = reconnect_time;
+}
+
+void qemu_chr_set_reconnect_time(Chardev *chr, int64_t reconnect_time)
+{
+    ChardevClass *cc = CHARDEV_GET_CLASS(chr);
+
+    if (cc->chr_set_reconnect_time) {
+        cc->chr_set_reconnect_time(chr, reconnect_time);
+    }
+}
+
 static void remove_hup_source(SocketChardev *s)
 {
     if (s->hup_source != NULL) {
@@ -591,7 +607,7 @@ static int tcp_chr_sync_read(Chardev *chr, const uint8_t *buf, int len)
     if (s->state != TCP_CHARDEV_STATE_DISCONNECTED) {
         qio_channel_set_blocking(s->ioc, false, NULL);
     }
-    if (size == 0) {
+    if (size == 0 && chr->chr_for_flag != CHR_FOR_VHOST_USER) {
         /* connection closed */
         tcp_chr_disconnect(chr);
     }
@@ -1585,6 +1601,7 @@ static void char_socket_class_init(ObjectClass *oc, void *data)
     cc->set_msgfds = tcp_set_msgfds;
     cc->chr_add_client = tcp_chr_add_client;
     cc->chr_add_watch = tcp_chr_add_watch;
+    cc->chr_set_reconnect_time = tcp_chr_set_reconnect_time;
     cc->chr_update_read_handler = tcp_chr_update_read_handler;
 
     object_class_property_add(oc, "addr", "SocketAddress",
diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
index 30379d2ca4..a60f7cef9a 100644
--- a/hw/net/vhost_net.c
+++ b/hw/net/vhost_net.c
@@ -376,7 +376,9 @@ int vhost_net_start(VirtIODevice *dev, NetClientState *ncs,
             goto err_start;
         }
 
-        if (peer->vring_enable) {
+	/* ovs needs to restore all states of vring */
+        if (peer->vring_enable ||
+	    ncs[i].peer->info->type == NET_CLIENT_DRIVER_VHOST_USER) {
             /* restore vring enable state */
             r = vhost_set_vring_enable(peer, peer->vring_enable);
 
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index c265e9e92c..fc2b1b81c9 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -1926,9 +1926,15 @@ static int vhost_user_backend_init(struct vhost_dev *dev, void *opaque,
     uint64_t features, protocol_features, ram_slots;
     struct vhost_user *u;
     int err;
+    Chardev *chr;
 
     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
 
+    chr = qemu_chr_fe_get_driver(((VhostUserState *)opaque)->chr);
+    if (chr) {
+        chr->chr_for_flag = CHR_FOR_VHOST_USER;
+    }
+
     u = g_new0(struct vhost_user, 1);
     u->user = opaque;
     u->dev = dev;
diff --git a/include/chardev/char.h b/include/chardev/char.h
index a319b5fdff..f388d4b109 100644
--- a/include/chardev/char.h
+++ b/include/chardev/char.h
@@ -14,6 +14,8 @@
 #define IAC_SB 250
 #define IAC 255
 
+#define CHR_FOR_VHOST_USER     0x32a1
+
 /* character device */
 typedef struct CharBackend CharBackend;
 
@@ -70,6 +72,7 @@ struct Chardev {
     GSource *gsource;
     GMainContext *gcontext;
     DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
+    int chr_for_flag;
 };
 
 /**
@@ -227,6 +230,16 @@ int qemu_chr_write(Chardev *s, const uint8_t *buf, int len, bool write_all);
 #define qemu_chr_write_all(s, buf, len) qemu_chr_write(s, buf, len, true)
 int qemu_chr_wait_connected(Chardev *chr, Error **errp);
 
+/**
+ * @qemu_chr_set_reconnect_time:
+ *
+ * Set reconnect time for char disconnect.
+ * Currently, only vhost user will call it.
+ *
+ * @reconnect_time the reconnect_time to be set
+ */
+void qemu_chr_set_reconnect_time(Chardev *chr, int64_t reconnect_time);
+
 #define TYPE_CHARDEV "chardev"
 OBJECT_DECLARE_TYPE(Chardev, ChardevClass, CHARDEV)
 
@@ -306,6 +319,9 @@ struct ChardevClass {
 
     /* handle various events */
     void (*chr_be_event)(Chardev *s, QEMUChrEvent event);
+
+    /* set reconnect time */
+    void (*chr_set_reconnect_time)(Chardev *chr, int64_t reconnect_time);
 };
 
 Chardev *qemu_chardev_new(const char *id, const char *typename,
diff --git a/net/vhost-user.c b/net/vhost-user.c
index b1a0247b59..d1aefcb9aa 100644
--- a/net/vhost-user.c
+++ b/net/vhost-user.c
@@ -21,6 +21,8 @@
 #include "qemu/option.h"
 #include "trace.h"
 
+#define VHOST_USER_RECONNECT_TIME (3)
+
 typedef struct NetVhostUserState {
     NetClientState nc;
     CharBackend chr; /* only queue index 0 */
@@ -287,6 +289,7 @@ static void net_vhost_user_event(void *opaque, QEMUChrEvent event)
     trace_vhost_user_event(chr->label, event);
     switch (event) {
     case CHR_EVENT_OPENED:
+        qemu_chr_set_reconnect_time(chr, VHOST_USER_RECONNECT_TIME);
         if (vhost_user_start(queues, ncs, s->vhost_user) < 0) {
             qemu_chr_fe_disconnect(&s->chr);
             return;
-- 
2.27.0