Sometimes it is necessary to test whether virtio-net can send and receive
packets
normally, just as e1000 does. This patch adds loopback for virtio-net, when the
command 'VIRTIO_NET_CTRL_LOOPBACK_SET' is sent from front-end driver(such as
virtio-net driver in linux.git), virtio-net goes into loopback mode, and the
test
above can be executed, then command 'VIRTIO_NET_CTRL_LOOPBACK_UNSET' can make
virtio-net go back to previous state.
Signed-off-by: Hengjinxiao <hjxiaoh...@gmail.com>
---
hw/net/virtio-net.c | 26 +++++++++++++++++++++++---
include/hw/virtio/virtio-net.h | 9 +++++++++
include/hw/virtio/virtio.h | 1 +
include/net/net.h | 1 +
net/net.c | 7 +++++--
5 files changed, 39 insertions(+), 5 deletions(-)
diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index 268eff9..ca313f4 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -778,6 +778,22 @@ static int virtio_net_handle_mq(VirtIONet *n, uint8_t cmd,
return VIRTIO_NET_OK;
}
+
+static int virtio_net_handle_loopback(VirtIONet *n, uint8_t cmd,
+ struct iovec *iov, unsigned int iov_cnt)
+{
+ VirtIODevice *vdev = VIRTIO_DEVICE(n);
+ if (cmd == VIRTIO_NET_CTRL_LOOPBACK_SET) {
+ vdev->loopback = 1;
+ return VIRTIO_NET_OK;
+ } else if (cmd == VIRTIO_NET_CTRL_LOOPBACK_UNSET) {
+ vdev->loopback = 0;
+ return VIRTIO_NET_OK;
+ } else {
+ return VIRTIO_NET_ERR;
+ }
+}
+
static void virtio_net_handle_ctrl(VirtIODevice *vdev, VirtQueue *vq)
{
VirtIONet *n = VIRTIO_NET(vdev);
@@ -813,6 +829,8 @@ static void virtio_net_handle_ctrl(VirtIODevice *vdev,
VirtQueue *vq)
status = virtio_net_handle_mq(n, ctrl.cmd, iov, iov_cnt);
} else if (ctrl.class == VIRTIO_NET_CTRL_GUEST_OFFLOADS) {
status = virtio_net_handle_offloads(n, ctrl.cmd, iov, iov_cnt);
+ } else if (ctrl.class == VIRTIO_NET_CTRL_LOOPBACK) {
+ status = virtio_net_handle_loopback(n, ctrl.cmd, iov, iov_cnt);
}
s = iov_from_buf(elem.in_sg, elem.in_num, 0, &status, sizeof(status));
@@ -1108,6 +1126,9 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q)
VirtQueueElement elem;
int32_t num_packets = 0;
int queue_index = vq2q(virtio_get_queue_index(q->tx_vq));
+ NetClientState *sender = qemu_get_subqueue(n->nic, queue_index);
+
+ sender->loopback = vdev->loopback;
if (!(vdev->status & VIRTIO_CONFIG_S_DRIVER_OK)) {
return num_packets;
}
@@ -1156,9 +1177,8 @@ static int32_t virtio_net_flush_tx(VirtIONetQueue *q)
}
len = n->guest_hdr_len;
-
- ret = qemu_sendv_packet_async(qemu_get_subqueue(n->nic, queue_index),
- out_sg, out_num, virtio_net_tx_complete);
+
+ ret = qemu_sendv_packet_async(sender, out_sg, out_num,
+ virtio_net_tx_complete);
if (ret == 0) {
virtio_queue_set_notification(q->tx_vq, 0);
q->async_tx.elem = elem;
diff --git a/include/hw/virtio/virtio-net.h b/include/hw/virtio/virtio-net.h
index 6ceb5aa..24e56bf 100644
--- a/include/hw/virtio/virtio-net.h
+++ b/include/hw/virtio/virtio-net.h
@@ -257,6 +257,15 @@ struct virtio_net_ctrl_mq {
#define VIRTIO_NET_CTRL_GUEST_OFFLOADS 5
#define VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET 0
+ /*
+ * Control Loopback
+ *
+ * The command VIRTIO_NET_CTRL_LOOPBACK_SET is used to require the device
+ * come into loopback state.
+ */
+#define VIRTIO_NET_CTRL_LOOPBACK 6
+ #define VIRTIO_NET_CTRL_LOOPBACK_SET 0
+ #define VIRTIO_NET_CTRL_LOOPBACK_UNSET 1
#define DEFINE_VIRTIO_NET_FEATURES(_state, _field) \
DEFINE_PROP_BIT("any_layout", _state, _field, VIRTIO_F_ANY_LAYOUT,
true), \
DEFINE_PROP_BIT("csum", _state, _field, VIRTIO_NET_F_CSUM, true), \
diff --git a/include/hw/virtio/virtio.h b/include/hw/virtio/virtio.h
index a60104c..219e0d2 100644
--- a/include/hw/virtio/virtio.h
+++ b/include/hw/virtio/virtio.h
@@ -128,6 +128,7 @@ struct VirtIODevice
VMChangeStateEntry *vmstate;
char *bus_name;
uint8_t device_endian;
+ uint8_t loopback;
};
typedef struct VirtioDeviceClass {
diff --git a/include/net/net.h b/include/net/net.h
index ed594f9..ce66b86 100644
--- a/include/net/net.h
+++ b/include/net/net.h
@@ -89,6 +89,7 @@ struct NetClientState {
NetClientDestructor *destructor;
unsigned int queue_index;
unsigned rxfilter_notify_enabled:1;
+ int loopback;
};
typedef struct NICState {
diff --git a/net/net.c b/net/net.c
index 6d930ea..f4c1ef4 100644
--- a/net/net.c
+++ b/net/net.c
@@ -611,8 +611,11 @@ ssize_t qemu_sendv_packet_async(NetClientState *sender,
if (sender->link_down || !sender->peer) {
return iov_size(iov, iovcnt);
}
-
- queue = sender->peer->incoming_queue;
+ if (sender->loopback) {
+ queue = sender->incoming_queue;
+ } else {
+ queue = sender->peer->incoming_queue;
+ }
return qemu_net_queue_send_iov(queue, sender,
QEMU_NET_PACKET_FLAG_NONE,
--
1.8.3.2
