[Qemu-devel] [PATCH RFC 4/7] net/filter: Introduce a helper to add a filter to the netdev

[zhanghailiang]

Signed-off-by: zhanghailiang <address@hidden>
---
 include/net/filter.h |  5 +++++
 net/filter.c         | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+)

diff --git a/include/net/filter.h b/include/net/filter.h
index d797ee4..c7bd8f9 100644
--- a/include/net/filter.h
+++ b/include/net/filter.h
@@ -81,4 +81,9 @@ static inline bool qemu_need_skip_netfilter(NetFilterState 
*nf)
 
 void netfilter_print_info(NetFilterState *nf, char *output_str, int size);
 
+void netdev_add_filter(const char *netdev_id,
+                       const char *filter_type,
+                       const char *id,
+                       Error **errp);
+
 #endif /* QEMU_NET_FILTER_H */
diff --git a/net/filter.c b/net/filter.c
index f4933cc..4d96301 100644
--- a/net/filter.c
+++ b/net/filter.c
@@ -16,6 +16,10 @@
 #include "qom/object_interfaces.h"
 #include "qemu/iov.h"
 #include "qapi/string-output-visitor.h"
+#include "qapi/qmp/qdict.h"
+#include "qapi/qmp-output-visitor.h"
+#include "qapi/qmp-input-visitor.h"
+#include "monitor/monitor.h"
 
 ssize_t qemu_netfilter_receive(NetFilterState *nf,
                                NetFilterDirection direction,
@@ -232,6 +236,65 @@ static void netfilter_complete(UserCreatable *uc, Error 
**errp)
     QTAILQ_INSERT_TAIL(&nf->netdev->filters, nf, next);
 }
 
+/*
+* This will be used by COLO or MC FT, for which they will need
+* to buffer the packets of VM's net devices, Here we add a default
+* buffer filter for each netdev. The name of default buffer filter is
+* 'nop'
+*/
+void netdev_add_filter(const char *netdev_id,
+                       const char *filter_type,
+                       const char *id,
+                       Error **errp)
+{
+    QmpOutputVisitor *qov;
+    QmpInputVisitor *qiv;
+    Visitor *ov, *iv;
+    QObject *obj = NULL;
+    QDict *qdict;
+    void *dummy = NULL;
+    NetClientState *nc = qemu_find_netdev(netdev_id);
+    Error *err = NULL;
+
+    /* FIXME: Not support multiple queues */
+    if (!nc || nc->queue_index > 1) {
+        return;
+    }
+    /* Not support vhost-net */
+    if (get_vhost_net(nc)) {
+        return;
+    }
+
+    qov = qmp_output_visitor_new();
+    ov = qmp_output_get_visitor(qov);
+    visit_start_struct(ov,  &dummy, NULL, NULL, 0, &err);
+    if (err) {
+        goto out;
+    }
+    visit_type_str(ov, &nc->name, "netdev", &err);
+    if (err) {
+        goto out;
+    }
+    visit_end_struct(ov, &err);
+    if (err) {
+        goto out;
+    }
+    obj = qmp_output_get_qobject(qov);
+    g_assert(obj != NULL);
+    qdict = qobject_to_qdict(obj);
+    qmp_output_visitor_cleanup(qov);
+
+    qiv = qmp_input_visitor_new(obj);
+    iv = qmp_input_get_visitor(qiv);
+    object_add(filter_type, id, qdict, iv, &err);
+    qmp_input_visitor_cleanup(qiv);
+    qobject_decref(obj);
+out:
+    if (err) {
+        error_propagate(errp, err);
+    }
+}
+
 static void netfilter_finalize(Object *obj)
 {
     NetFilterState *nf = NETFILTER(obj);
-- 
1.8.3.1