mpmd,transport,prefs: Add xport_mgr for dpdk_zero_copy

Add configuration sections to the UHD config file for NIC entries. Keys
are based on MAC addresses, and the entries beneath the section describe
which CPU and I/O thread to use for the NIC and its IPv4 address.

Make ring sizes configurable for uhd-dpdk. Ring size is now an argument
for packet buffers. Note that the maximum number of available buffers
is still determined at init!

Add ability to receive broadcasts to uhd-dpdk. This is controllable by
a boolean in the sockarg during socket creation. dpdk_zero_copy will
filter broadcast packets out.

Add dpdk_simple transport (to mirror udp_simple). This transport allows
receiving from broadcast addresses, but it only permits one outstanding
buffer at a time.

Fix IP checksum handling in UHD-DPDK.
TX checksums were not being calculated in the NIC, and in RX, the check
for IP checksums allowed values of zero (reported as none). Now packets
with bad IP checksums will be dropped.

1 files changed, 12 insertions, 7 deletions

diff --git a/host/lib/transport/uhd-dpdk/uhd_dpdk_driver.c b/host/lib/transport/uhd-dpdk/uhd_dpdk_driver.c
index f603f1f8f..61ed836df 100644
--- a/host/lib/transport/uhd-dpdk/uhd_dpdk_driver.c
+++ b/host/lib/transport/uhd-dpdk/uhd_dpdk_driver.c
@@ -43,7 +43,6 @@ int _uhd_dpdk_arp_reply(struct uhd_dpdk_port *port, struct arp_hdr *arp_req)
 
     mbuf->pkt_len = 42;
     mbuf->data_len = 42;
-    mbuf->ol_flags = PKT_TX_IP_CKSUM;
 
     if (rte_eth_tx_burst(port->id, 0, &mbuf, 1) != 1) {
         RTE_LOG(WARNING, RING, "%s: TX descriptor ring is full\n", __func__);
@@ -125,7 +124,6 @@ int _uhd_dpdk_arp_request(struct uhd_dpdk_port *port, uint32_t ip)
 
     mbuf->pkt_len = 42;
     mbuf->data_len = 42;
-    mbuf->ol_flags = PKT_TX_IP_CKSUM;
 
     if (rte_eth_tx_burst(port->id, 0, &mbuf, 1) != 1) {
         RTE_LOG(WARNING, RING, "%s: TX descriptor ring is full\n", __func__);
@@ -135,7 +133,8 @@ int _uhd_dpdk_arp_request(struct uhd_dpdk_port *port, uint32_t ip)
     return 0;
 }
 
-int _uhd_dpdk_process_udp(struct uhd_dpdk_port *port, struct rte_mbuf *mbuf, struct udp_hdr *pkt)
+int _uhd_dpdk_process_udp(struct uhd_dpdk_port *port, struct rte_mbuf *mbuf,
+                          struct udp_hdr *pkt, bool bcast)
 {
     int status = 0;
     struct uhd_dpdk_ipv4_5tuple ht_key = {
@@ -155,6 +154,10 @@ int _uhd_dpdk_process_udp(struct uhd_dpdk_port *port, struct rte_mbuf *mbuf, str
     }
 
     struct uhd_dpdk_udp_priv *pdata = (struct uhd_dpdk_udp_priv *) entry->sock->priv;
+    if (bcast && pdata->filter_bcast) {
+        // Filter broadcast packets if not listening
+        goto udp_rx_drop;
+    }
     status = rte_ring_enqueue(entry->sock->rx_ring, mbuf);
     if (entry->waiter) {
         _uhd_dpdk_waiter_wake(entry->waiter, port->parent);
@@ -172,14 +175,16 @@ udp_rx_drop:
     return status;
 }
 
-int _uhd_dpdk_process_ipv4(struct uhd_dpdk_port *port, struct rte_mbuf *mbuf, struct ipv4_hdr *pkt)
+int _uhd_dpdk_process_ipv4(struct uhd_dpdk_port *port, struct rte_mbuf *mbuf,
+                           struct ipv4_hdr *pkt)
 {
-    if (pkt->dst_addr != port->ipv4_addr) {
+    bool bcast = is_broadcast(port, pkt->dst_addr);
+    if (pkt->dst_addr != port->ipv4_addr && !bcast) {
         rte_pktmbuf_free(mbuf);
         return -ENODEV;
     }
     if (pkt->next_proto_id == 0x11) {
-        return _uhd_dpdk_process_udp(port, mbuf, (struct udp_hdr *) &pkt[1]);
+        return _uhd_dpdk_process_udp(port, mbuf, (struct udp_hdr *) &pkt[1], bcast);
     }
     rte_pktmbuf_free(mbuf);
     return -EINVAL;
@@ -417,7 +422,7 @@ static inline void _uhd_dpdk_rx_burst(struct uhd_dpdk_port *port)
             rte_pktmbuf_free(bufs[buf]);
             break;
         case ETHER_TYPE_IPv4:
-            if (ol_flags == PKT_RX_IP_CKSUM_BAD) { /* TODO: Track IP cksum errors? */
+            if (ol_flags & PKT_RX_IP_CKSUM_BAD) {
                 RTE_LOG(WARNING, RING, "Buf %d: Bad IP cksum\n", buf);
             } else {
                 _uhd_dpdk_process_ipv4(port, bufs[buf], (struct ipv4_hdr *) l2_data);