1 files changed, 81 insertions, 0 deletions
diff --git a/lib/librte_gso/gso_udp4.c b/lib/librte_gso/gso_udp4.c
new file mode 100644
index 00000000..927dee12
--- /dev/null
+++ b/lib/librte_gso/gso_udp4.c
@@ -0,0 +1,81 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2018 Intel Corporation
+ */
+
+#include "gso_common.h"
+#include "gso_udp4.h"
+
+#define IPV4_HDR_MF_BIT (1U << 13)
+
+static inline void
+update_ipv4_udp_headers(struct rte_mbuf *pkt, struct rte_mbuf **segs,
+		uint16_t nb_segs)
+{
+	struct ipv4_hdr *ipv4_hdr;
+	uint16_t frag_offset = 0, is_mf;
+	uint16_t l2_hdrlen = pkt->l2_len, l3_hdrlen = pkt->l3_len;
+	uint16_t tail_idx = nb_segs - 1, length, i;
+
+	/*
+	 * Update IP header fields for output segments. Specifically,
+	 * keep the same IP id, update fragment offset and total
+	 * length.
+	 */
+	for (i = 0; i < nb_segs; i++) {
+		ipv4_hdr = rte_pktmbuf_mtod_offset(segs[i], struct ipv4_hdr *,
+			l2_hdrlen);
+		length = segs[i]->pkt_len - l2_hdrlen;
+		ipv4_hdr->total_length = rte_cpu_to_be_16(length);
+
+		is_mf = i < tail_idx ? IPV4_HDR_MF_BIT : 0;
+		ipv4_hdr->fragment_offset =
+			rte_cpu_to_be_16(frag_offset | is_mf);
+		frag_offset += ((length - l3_hdrlen) >> 3);
+	}
+}
+
+int
+gso_udp4_segment(struct rte_mbuf *pkt,
+		uint16_t gso_size,
+		struct rte_mempool *direct_pool,
+		struct rte_mempool *indirect_pool,
+		struct rte_mbuf **pkts_out,
+		uint16_t nb_pkts_out)
+{
+	struct ipv4_hdr *ipv4_hdr;
+	uint16_t pyld_unit_size, hdr_offset;
+	uint16_t frag_off;
+	int ret;
+
+	/* Don't process the fragmented packet */
+	ipv4_hdr = rte_pktmbuf_mtod_offset(pkt, struct ipv4_hdr *,
+			pkt->l2_len);
+	frag_off = rte_be_to_cpu_16(ipv4_hdr->fragment_offset);
+	if (unlikely(IS_FRAGMENTED(frag_off))) {
+		pkts_out[0] = pkt;
+		return 1;
+	}
+
+	/*
+	 * UDP fragmentation is the same as IP fragmentation.
+	 * Except the first one, other output packets just have l2
+	 * and l3 headers.
+	 */
+	hdr_offset = pkt->l2_len + pkt->l3_len;
+
+	/* Don't process the packet without data. */
+	if (unlikely(hdr_offset + pkt->l4_len >= pkt->pkt_len)) {
+		pkts_out[0] = pkt;
+		return 1;
+	}
+
+	pyld_unit_size = gso_size - hdr_offset;
+
+	/* Segment the payload */
+	ret = gso_do_segment(pkt, hdr_offset, pyld_unit_size, direct_pool,
+			indirect_pool, pkts_out, nb_pkts_out);
+	if (ret > 1)
+		update_ipv4_udp_headers(pkt, pkts_out, ret);
+
+	return ret;
+}