drivers: net: loopback: Simulate real hw device
Instead of passing net_pkt as is to the receiving side of the
interface, clone the sent packet and drop the sent one.
This is needed mainly in TCP where passing the same packet from
sending to receiving side is causing havoc.
Signed-off-by: Jukka Rissanen <jukka.rissanen@linux.intel.com>
diff --git a/drivers/net/loopback.c b/drivers/net/loopback.c
index a5371f4..5232428 100644
--- a/drivers/net/loopback.c
+++ b/drivers/net/loopback.c
@@ -36,6 +36,7 @@
static int loopback_send(struct net_if *iface, struct net_pkt *pkt)
{
+ struct net_pkt *cloned;
int res;
if (!pkt->frags) {
@@ -63,14 +64,30 @@
net_ipaddr_copy(&NET_IPV4_HDR(pkt)->dst, &addr);
}
- res = net_recv_data(iface, pkt);
- if (res < 0) {
- SYS_LOG_ERR("Data receive failed.");
- net_pkt_unref(pkt);
- return res;
+ /* We should simulate normal driver meaning that if the packet is
+ * properly sent (which is always in this driver), then the packet
+ * must be dropped. This is very much needed for TCP packets where
+ * the packet is reference counted in various stages of sending.
+ */
+ cloned = net_pkt_clone(pkt, MSEC(100));
+ if (!cloned) {
+ res = -ENOMEM;
+ goto out;
}
- return 0;
+ res = net_recv_data(iface, cloned);
+ if (res < 0) {
+ SYS_LOG_ERR("Data receive failed.");
+ goto out;
+ }
+
+out:
+ net_pkt_unref(pkt);
+
+ /* Let the receiving thread run now */
+ k_yield();
+
+ return res;
}
static struct net_if_api loopback_if_api = {
